WorldWideScience

Sample records for hub fairing drag

  1. Kevlar/PMR-15 reduced drag DC-9 reverser stang fairing

    Science.gov (United States)

    Kawai, R. T.

    1982-01-01

    A reduced drag fairing for the afterbody enclosing the thrust reverser actuators on the DC-9 has been developed with Kevlar-49/PMR-15 advanced composite material. The improved fairing reduces airplane drag 1% compared to the production baseline. Use of composites reduces weight 40% compared to an equivalent metal fairing. The Kevlar-49/PMR-15 advanced composite is an organic matrix material system that can be used at temperatures up to 500 F.

  2. Fair Topologies: Community Structures and Network Hubs Drive Emergence of Fairness Norms.

    Science.gov (United States)

    Mosleh, Mohsen; Heydari, Babak

    2017-06-02

    Fairness has long been argued to govern human behavior in a wide range of social, economic, and organizational activities. The sense of fairness, although universal, varies across different societies. In this study, using a computational model, we test the hypothesis that the topology of social interaction can causally explain some of the cross-societal variations in fairness norms. We show that two network parameters, namely, community structure, as measured by the modularity index, and network hubiness, represented by the skewness of degree distribution, have the most significant impact on emergence of collective fair behavior. These two parameters can explain much of the variations in fairness norms across societies and can also be linked to hypotheses suggested by earlier empirical studies in social and organizational sciences. We devised a multi-layered model that combines local agent interactions with social learning, thus enables both strategic behavior as well as diffusion of successful strategies. By applying multivariate statistics on the results, we obtain the relation between network structural features and the collective fair behavior.

  3. Development of a Kevlar/PMR-15 reduced drag DC-9 nacelle fairing

    Science.gov (United States)

    Kawai, R. T.; Hrach, F. J.

    1980-01-01

    The paper describes an advanced composite fairing designed to reduce drag on DC-9 nacelles as a part of the NASA Engine Component Improvement Program. This fairing is the aft enclosure for the thrust reverser actuator system on JT8D engine nacelles and is subjected to a 500 F exhaust flow during the reverse thrust. A reduced-drag configuration was developed by using in-flight tuft surveys for flow visualization in order to identify areas with low-quality flow, and then modifying the aerodynamic lines to improve the flow. A fabrication method for molding the part in an autoclave was developed; this material system is suitable for 500 F. The resultant composite fairing reduces the overall aircraft drag 1% with a weight reduction of 40% when compared with a metal component.

  4. Test Data Report, Low-Speed Wind Tunnel Drag Test of a 2/5 Scale Lockheed AH-56 Cheyenne Door-Hinge Hub

    Science.gov (United States)

    2016-07-01

    SPECIAL REPORT RDMR-AD-16-03 TEST DATA REPORT, LOW-SPEED WIND TUNNEL DRAG TEST OF A 2/5 SCALE LOCKHEED AH-56 CHEYENNE DOOR-HINGE HUB Robert D...TYPE AND DATES COVERED Final 4. TITLE AND SUBTITLE Test Data Report, Low-Speed Wind Tunnel Drag Test of a 2/5 Scale Lockheed AH-56 Cheyenne...Research, Development and Engineering Center (AMRDEC) conducted a drag test of a non-rotating 2/5 scale Lockheed AH-56 Cheyenne main rotor hub in

  5. Kevlar/PMR-15 polyimide matrix composite for a complex shaped DC-9 drag reduction fairing

    Science.gov (United States)

    Kawai, R. T.; Mccarthy, R. F.; Willer, M. S.; Hrach, F. J.

    1982-01-01

    The Aircraft Energy Efficiency (ACEE) Program was established by NASA to improve the fuel efficiency of commercial transport aircraft and thereby to reduce the amount of fuel consumed by the air transportation industry. One of the final items developed by the program is an improved fairing which is the aft closure for the thrust reverser actuators on the JT8D nacelles on DC-9 aircraft. The reduced-drag fairing uses, in the interest of weight savings, an advanced composite construction. The composite material contains Kevlar 49 fibers in a PMR-15 matrix. Attention is given to the aerodynamic configuration, the material system, and aspects of fabrication development.

  6. faire ?

    African Journals Online (AJOL)

    africaine', elle s'intéressait à une histoire qui devait d'abord leur restituer un ..... définition de faire de l'histoire » des courants historiographiques actuels”. ..... nent — la production africaine du monde au plan géographique et humain n et.

  7. Fair

    CERN Multimedia

    2005-01-01

    The 'Presses Polytechniques Universitaires Romandes' is organising a book exhibition. The major topics covered will be science and technology. The fair will take place in the foyer of the main building (building 60), and will be open from 10am - 4pm on 5th July 2005.

  8. Solving Hub Network Problem Using Genetic Algorithm

    Directory of Open Access Journals (Sweden)

    Mursyid Hasan Basri

    2012-01-01

    non-linearity, so there is no guarantee to find the optimal solution. Moreover, it has generated a great number of variables. Therefore, a heuristic method is required to find near optimal solution with reasonable computation time. For this reason, a genetic algorithm (GA-based procedure is proposed. The proposed procedure then is applied to the same problem as discussed in the basic model. The results indicated that there is significant improvement on hub locations. Flows are successfully consolidated to several big ports as expected. With regards to spoke allocations, however, spokes are not fairly allocated.Keywords: Hub and Spoke Model; Marine Transportation; Genetic Algorithm

  9. Solving Hub Network Problem Using Genetic Algorithm

    Directory of Open Access Journals (Sweden)

    Mursyid Hasan Basri

    2012-01-01

    non-linearity, so there is no guarantee to find the optimal solution. Moreover, it has generated a great number of variables. Therefore, a heuristic method is required to find near optimal solution with reasonable computation time. For this reason, a genetic algorithm (GA-based procedure is proposed. The proposed procedure then is applied to the same problem as discussed in the basic model. The results indicated that there is significant improvement on hub locations. Flows are successfully consolidated to several big ports as expected. With regards to spoke allocations, however, spokes are not fairly allocated.Keywords: Hub and Spoke Model; Marine Transportation; Genetic Algorithm

  10. Innovation hubs

    DEFF Research Database (Denmark)

    O´Hara, J.; Hansen, Poul H. Kyvsgård; Turner, N.

    2008-01-01

    "Whilst ‘incremental innovation' is an imperative for the short-to-medium term success of a company, there is also a need for companies to engage in innovation activity that goes beyond the incremental in order to guarantee long-term success. However, such ‘radical innovation' (RI) poses new...... challenges and requires new competencies, some of which may conflict with existing best-practices for incremental innovations. ‘Innovation hubs' are a type of organisational structure dedicated to RI projects that have been used by companies to manage these conflicts by maintaining a certain degree...... of separation from the culture and routines of the mainstream organisation. Unfortunately, it would appear that many attempts to set-up innovation hubs have ended in failure within a few years; not before considerable time, effort and resource has been expended. This paper reports on a study of six innovation...

  11. Innovation hubs

    DEFF Research Database (Denmark)

    O´Hara, J.; Hansen, Poul H. Kyvsgård; Turner, N.

    2008-01-01

    "Whilst ‘incremental innovation' is an imperative for the short-to-medium term success of a company, there is also a need for companies to engage in innovation activity that goes beyond the incremental in order to guarantee long-term success. However, such ‘radical innovation' (RI) poses new...... challenges and requires new competencies, some of which may conflict with existing best-practices for incremental innovations. ‘Innovation hubs' are a type of organisational structure dedicated to RI projects that have been used by companies to manage these conflicts by maintaining a certain degree...... of separation from the culture and routines of the mainstream organisation. Unfortunately, it would appear that many attempts to set-up innovation hubs have ended in failure within a few years; not before considerable time, effort and resource has been expended. This paper reports on a study of six innovation...

  12. Natural Gas Market Hubs

    Data.gov (United States)

    Department of Homeland Security — A hub is a physical transfer point for natural gas where several pipelines are connected. A market center is a hub where the operator offers services that facilitate...

  13. Quadratic Assignment of Hubs in p-Hub Median Problem

    DEFF Research Database (Denmark)

    Gelareh, Shahin

    We introduce Generalized p-Hub Median Problem (GpHMP) that seeks to locate p hub nodes and install p distinct hub facilities/operators on the hubs while discount factor resulted by consolidation of flow on the hub links depends on the facilities/operators that are installed/operating on both hub...... nodes end-point. In contrast, in traditional hub location problems it is commonly assumed that all the hub facilities share a similar characteristic and economy of scale resulted by consolidation of flow over hub edges is not directly relevant to the hub facilities being installed at both end...

  14. Virtual Campus Hub technology

    DEFF Research Database (Denmark)

    Vercoulen, Frank; Badger, Merete; Monaco, Lucio;

    This deliverable briefly describes which technological components have been delivered for the Virtual Campus Hub and how they can be used. A detailed discussion of the technical details of the components, how they were realized and how they fit the VCH concept can be found in deliverables D5.......4. Virtual Campus Hub Technology Evaluation Report and D6.7 The Virtual Campus Hub Concept....

  15. Aircraft Propeller Hub Repair

    Energy Technology Data Exchange (ETDEWEB)

    Muth, Thomas R. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Peter, William H. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-02-13

    The team performed a literature review, conducted residual stress measurements, performed failure analysis, and demonstrated a solid state additive manufacturing repair technique on samples removed from a scrapped propeller hub. The team evaluated multiple options for hub repair that included existing metal buildup technologies that the Federal Aviation Administration (FAA) has already embraced, such as cold spray, high velocity oxy-fuel deposition (HVOF), and plasma spray. In addition the team helped Piedmont Propulsion Systems, LLC (PPS) evaluate three potential solutions that could be deployed at different stages in the life cycle of aluminum alloy hubs, in addition to the conventional spray coating method for repair. For new hubs, a machining practice to prevent fretting with the steel drive shaft was recommended. For hubs that were refurbished with some material remaining above the minimal material condition (MMC), a silver interface applied by an electromagnetic pulse additive manufacturing method was recommended. For hubs that were at or below the MMC, a solid state additive manufacturing technique using ultrasonic welding (UW) of thin layers of 7075 aluminum to the hub interface was recommended. A cladding demonstration using the UW technique achieved mechanical bonding of the layers showing promise as a viable repair method.

  16. Judging Fairs Fairly.

    Science.gov (United States)

    McBride, John W.; Silverman, Fredrick L.

    1988-01-01

    Discusses some of the problems associated with winners and losers at science fairs. Presents two alternatives to the traditional prize system: "The Scouting Concept" and "The County Fair Concept." Stresses the values and learnings that are associated with successful fairs. (CW)

  17. Gastronomiske drags

    DEFF Research Database (Denmark)

    Leer, Jonatan

    2013-01-01

    with Jennifer Parson and Clarissa Dickson Wright (1996-1999). I will argue that the two self-declared fat women can be read as “gastronomic drags” by their transgression of a “recognizable” feminine way of “doing food”. The article is theoretically informed by the reflections on drag as subversive practice...... of appearing either too radical or not radical enough. The article concludes with some reflections on the development of the cooking show as a site for gendered negotiation from the 90’s and today....

  18. Twin Hub Network (poster)

    NARCIS (Netherlands)

    Kreutzberger, E.D.; Konings, J.W.

    2014-01-01

    Twin hub network, a European Interreg IVB project, aims at making intermodal rail transport within, to and from North West Europe more competitive, in particular between seaports and inland terminals. Improving rail competitiveness enables to shift freight flows from road to rail, providing a more s

  19. Deconstructing Hub Drag. Part 2. Computational Development and Anaysis

    Science.gov (United States)

    2013-09-30

    Because the hot - wire anemometry locations were not known until after the experiment, these runs were continued, without user intervention, until...adaptations or simulation length may be needed in the computations. Recent experiments with hot - wire anemometry were analyzed, raising additional questions...The hot - wire anemometry data were provided in the form of velocities of the form V^ as well as perturbations of this velocity.2 The quantity V/, is

  20. Methods of reducing vehicle aerodynamic drag

    Energy Technology Data Exchange (ETDEWEB)

    Sirenko V.; Rohatgi U.

    2012-07-08

    A small scale model (length 1710 mm) of General Motor SUV was built and tested in the wind tunnel for expected wind conditions and road clearance. Two passive devices, rear screen which is plate behind the car and rear fairing where the end of the car is aerodynamically extended, were incorporated in the model and tested in the wind tunnel for different wind conditions. The conclusion is that rear screen could reduce drag up to 6.5% and rear fairing can reduce the drag by 26%. There were additional tests for front edging and rear vortex generators. The results for drag reduction were mixed. It should be noted that there are aesthetic and practical considerations that may allow only partial implementation of these or any drag reduction options.

  1. Transport hub flow modelling

    OpenAIRE

    Despagne, Wilfried; Frenod, Emmanuel

    2014-01-01

    Purpose: The purpose of this paper is to investigate the road freight haulage activity. Using the physical and data flow information from a freight forwarder, we intend to model the flow of inbound and outbound goods in a freight transport hub. Approach: This paper presents the operation of a road haulage group. To deliver goods within two days to any location in France, a haulage contractor needs to be part of a network. This network handles the processing of both physical goods and data. We...

  2. GitHub Android

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    代码托管仓库GitHub发布了官方,Android客户端,手机和平板用户可以从GoogleP1ay下载。它的出现,将方便更多用户融入GitHub社区。GitHubAndroid本身也是开源软件,其源代码可以从GitHub浏览。此前,GitHub已经推出了Windows和Mac版客户端。

  3. PORTS WRESTLE FOR HUB STATUS

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    Due to the fact that there has been nocontainer transport hub port in NorthernChina,northern ports are striving fordevelopment and trying to secure a positionof being the hub port in Northern Chinaahead of others. According to media reports,EasternChina’s Shandong Province will invest 5billion yuan(US$604 million)in buildinga Qingdao international shipping hub thatisbased on existing ports in theShandong Peninsula.

  4. Automated design of minimum drag light aircraft fuselages and nacelles

    Science.gov (United States)

    Smetana, F. O.; Fox, S. R.; Karlin, B. E.

    1982-01-01

    The constrained minimization algorithm of Vanderplaats is applied to the problem of designing minimum drag faired bodies such as fuselages and nacelles. Body drag is computed by a variation of the Hess-Smith code. This variation includes a boundary layer computation. The encased payload provides arbitrary geometric constraints, specified a priori by the designer, below which the fairing cannot shrink. The optimization may include engine cooling air flows entering and exhausting through specific port locations on the body.

  5. Exam fairness

    CERN Document Server

    Bouville, Mathieu

    2008-01-01

    It is widely agreed that exams must be fair; yet what this exactly means is not made clear. One may mean fairness of treatment, but this merely propagates the fairness or unfairness of pre-existing rules. Fairness of opportunity on the other hand necessarily leads to identical grades for everyone, which clearly makes it inapplicable. Neither view is helpful to make decisions on competing claims: fairness of treatment ignores the problem and fairness of opportunity holds all claims to be equally valid. To escape this deadlock one needs an external criterion to replace fairness viewed as student-student comparison. Keywords: assessment; bias; engineering education; examinations; grading; justice; tests

  6. How Fair is Fair Trade?

    NARCIS (Netherlands)

    Vaal, A. de; Maseland, R.K.J.

    2001-01-01

    This paper investigates to what extent fair trade programmes, are indeed fair . This is accomplished by comparing fair trade with free trade and protectionist trade regimes on their compliance of the criteria set by the fair trade movement itself. This comparison is made using comparative cost base

  7. How Fair is Fair Trade?

    NARCIS (Netherlands)

    Maseland, R.K.J.; Vaal, A. de

    2002-01-01

    This paper investigates to what extent fair trade programmes, are indeed ‘fair.’ This is accomplished by comparing fair trade with free trade and protectionist trade regimes on their compliance of the criteria set by the fair trade movement itself. This comparison is made using comparative cost base

  8. How Fair is Fair Trade?

    NARCIS (Netherlands)

    Vaal, A. de; Maseland, R.K.J.

    2001-01-01

    This paper investigates to what extent fair trade programmes, are indeed fair . This is accomplished by comparing fair trade with free trade and protectionist trade regimes on their compliance of the criteria set by the fair trade movement itself. This comparison is made using comparative cost base

  9. How Fair is Fair Trade?

    NARCIS (Netherlands)

    Maseland, R.K.J.; Vaal, A. de

    2002-01-01

    This paper investigates to what extent fair trade programmes, are indeed ‘fair.’ This is accomplished by comparing fair trade with free trade and protectionist trade regimes on their compliance of the criteria set by the fair trade movement itself. This comparison is made using comparative cost base

  10. Indico: A Collaboration Hub

    CERN Document Server

    Ferreira, P; Bossy, C; Gonzalez, J B; Pugh, M; Resco, A; Trzaskoma, J; Wachter, C

    2012-01-01

    Since 2009, the development of Indico has focused on usability, performance and new features, especially the ones related to meeting collaboration. Usability studies have resulted in the biggest change Indico has experienced up to now, a new web layout that makes user experience better. Performance improvements were also a key goal since 2010; the main features of Indico have been optimized remarkably. Along with usability and performance, new features have been added to Indico such as webchat integration, video services bookings, webcast and recording requests, designed to really reinforce Indico position as the main hub for all CERN collaboration services, and many others which aim is to complete the conference lifecycle management. Indico development is also moving towards a broader collaboration where other institutes, hosting their own Indico instance, can contribute to the project in order make it a better and more complete tool.

  11. Aerodynamic Design of a Locomotive Fairing

    Science.gov (United States)

    Stucki, Chad; Maynes, Daniel

    2016-11-01

    Rising fuel cost has motivated increased fuel efficiency of freight trains. At cruising speed, the largest contributing factor to the fuel consumption is the aerodynamic drag. As a result of air stagnation at the front of the train and substantial flow separation behind, the leading locomotive and trailing railcar experience greater drag than intermediate cars. This work introduces the design of streamlined nose fairings to be attached to freight locomotives as a means of reducing the leading locomotive drag. The aerodynamic performance of each fairing design is modeled using a commercial CFD software package. The K-epsilon turbulence model is used, and fluid properties are equivalent to atmospheric air at standard conditions. A selection of isolated screening studies are performed, and a multidimensional regression is used to predict optimal-performing fairing designs. Between screening studies, careful examination of the flow field is performed to inspire subsequent fairing designs. Results are presented for 250 different nose fairings. The best performing fairing geometry predicts a nominal drag reduction of 17% on the lead locomotive in a train set. This drag reduction is expected to result in nearly 1% fuel savings for the entire train.

  12. Fair skoleledelse

    DEFF Research Database (Denmark)

    Larsen, Peter; Vestergaard, Bo

    2014-01-01

    relationelle strategiske ledelsesprocesser (RSL-processer) mellem ledelse og medarbejdere i organisationers strategiarbejde. I artiklens anden del oversættes den teoretiske del til et praksisorienteret ottefaset strategisk procesdesign: FAIR SKOLELEDELSE. FAIR SKOLELEDELSE er et strategisk tanke- og...

  13. Fair Trade

    OpenAIRE

    2007-01-01

    This paper deals with the behavior of fair trade organizations in an oligopolistic setting in which the vertically integrated fair trade firm produces a commodity which is a weak substitute for another commodity. Profit-maximizing oligopolists are vertically disintegrated and produce for both markets and the fair trade firm can charge a premium to consumers due to a "warm glow effect" that depends on the wage paid to fair trade producers. We show that trade integration will unambiguously incr...

  14. How Fair Is Actuarial Fairness?

    DEFF Research Database (Denmark)

    Landes, Xavier

    2015-01-01

    in exchange for the payment of premi- ums. In the insurance industry, the concept of actuarial fairness serves to establish what could be adequate, fair premiums. Accordingly, premiums paid by policyholders should match as closely as possible their risk exposure (i.e. their expected losses). Such premiums...... are the product of the probabilities of losses and the expected losses. This article presents a discussion of the fairness of actuarial fairness through three steps: (1) defining the concept based on its formulation within the insurance industry; (2) determining in which sense it may be about fairness; and (3......) raising some objections to the actual fairness of actu- arial fairness. The necessity of a normative evaluation of actuarial fairness is justified by the influence of the concept on the current reforms of public insurance systems and the fact that it highlights the question of the repartition of the gains...

  15. The Virtual Campus Hub Concept

    DEFF Research Database (Denmark)

    Badger, Merete; Prag, Sidsel-Marie Winther; Monaco, Lucio

    of Technology in Sweden, Politecnico di Torino in Italy, and Eindhoven University of Technology in the Netherlands. The project is partially funded by the European Commission under the 7th Framework Programme (project no. RI-283746). This report describes the final concept of Virtual Campus Hub. It gives...... an overview of the project achievements and recommends best practices for the use of the Virtual Campus Hub elements: a series of applications for online teaching and collaboration which are connected to a technical platform, the Virtual Campus Hub portal, using the European research infrastructure Géant/eduGAIN....

  16. How Fair are Fair Allocations?

    DEFF Research Database (Denmark)

    Wøhlk, Sanne; Kiilerich, Lone

    investigates the fairness of such allocations. Previous literature has applied numerous ways of measuring allocation fairness as well as numerous strategies for obtaining allocations. The goal of this paper is to study the fairness of allocations obtained by different allocation methods as viewed by different...... fairness measures. We hope that this will help guide future research towards a rational choice of allocation methods and measures....

  17. How fair is fair trade?

    NARCIS (Netherlands)

    Maseland, Robbert; Vaal, Albert de

    2001-01-01

    This paper investigates to what extent fair trade programmes, are indeed ‘fair’. This is accomplished by comparing fair trade with free trade and protectionist trade regimes on their compliance of the criteria set by the fair trade movement itself. This comparison is made using comparative cost base

  18. How fair is fair trade?

    NARCIS (Netherlands)

    Maseland, Robbert; Vaal, Albert de

    2001-01-01

    This paper investigates to what extent fair trade programmes, are indeed ‘fair’. This is accomplished by comparing fair trade with free trade and protectionist trade regimes on their compliance of the criteria set by the fair trade movement itself. This comparison is made using comparative cost

  19. How fair is fair trade?

    NARCIS (Netherlands)

    Maseland, Robbert; Vaal, Albert de

    2001-01-01

    This paper investigates to what extent fair trade programmes, are indeed ‘fair’. This is accomplished by comparing fair trade with free trade and protectionist trade regimes on their compliance of the criteria set by the fair trade movement itself. This comparison is made using comparative cost base

  20. A new transport hub

    CERN Multimedia

    Corinne Pralavorio

    2016-01-01

    CERN’s new Mobility Centre, allowing you to switch easily from one mode of transport to another, has just been officially opened.   Inauguration of the CERN Mobility Centre by Martin Steinacher, Director for Finance and Human Resources, and Lluis Miralles, Head of the SMB department. CERN’s new Mobility Centre, on the car park next to the Globe of Science and Innovation was officially opened on Tuesday, 22 March. The centre brings together all of CERN’s transport options in a single location. "Our aim is to create an intermodal hub where CERN users and personnel can switch from one mode of transport to another, and from CERN transport to public transport," explains Lluis Miralles, head of the Site Management and Buildings (SMB) department. The Mobility Centre incorporates the CERN bike and car rental services, the self-service car- and bike-sharing schemes, and SIXT car rental facilities (for long-distance journeys). It is located right ne...

  1. Drag Coefficient and Foam in Hurricane Conditions.

    Science.gov (United States)

    Golbraikh, E.; Shtemler, Y.

    2016-12-01

    he present study is motivated by recent findings of saturation and even decrease in the drag coefficient (capping) in hurricane conditions, which is accompanied by the production of a foam layer on the ocean surface. As it is difficult to expect at present a comprehensive numerical modeling of the drag coefficient saturation that is followed by wave breaking and foam production, there is no complete confidence and understanding of the saturation phenomenon. Our semi-empirical model is proposed for the estimation of the foam impact on the variation of the effective drag coefficient, Cd , with the reference wind speed U10 in stormy and hurricane conditions. The proposed model treats the efficient air-sea aerodynamic roughness length as a sum of two weighted aerodynamic roughness lengths for the foam-free and foam-covered conditions. On the available optical and radiometric measurements of the fractional foam coverage,αf, combined with direct wind speed measurements in hurricane conditions, which provide the minimum of the effective drag coefficient, Cd for the sea covered with foam. The present model yields Cd10 versus U10 in fair agreement with that evaluated from both open-ocean and laboratory measurements of the vertical variation of mean wind speed in the range of U10 from low to hurricane speeds. The present approach opens opportunities for drag coefficient modeling in hurricane conditions and hurricane intensity estimation by the foam-coverage value using optical and radiometric measurements.

  2. Fair Isle

    OpenAIRE

    2011-01-01

    An analyses of the name Fair Isle. It is argued that the name is likely to be linked to more than 20 other similar names, mostly Færøy in Norway, and that the etymology is from Old Norse fara and ferd, 'travel, journey'. The motive behind the names is the importance of these islands for travel, and Fair Isle between Orkney and Shetland exceptionally so.

  3. Fair Testing

    OpenAIRE

    1995-01-01

    We investigate the notion of fair testing, a formal testing theory in the style of De Nicola and Hennessy where divergences are disregarded as long as there are visible outgoing transitions. The usual testing theories, such as the standard model of failure pre-order, do not allow such fair interpretations because of the way in which they ensure their compositionality with respect to abstraction from observable actions. This feature is usually present in the form of a hiding-operator (CSP, ACP...

  4. Drag kings in the new wave: gender performance and participation.

    Science.gov (United States)

    Surkan, Kim

    2002-01-01

    In an examination of Midwestern drag king performers and communities that have emerged since the study by Volcano and Halberstam of king cultures in London, New York, and San Francisco, this article considers traditional and alternative ways of "doing drag," both performative and participatory, as a means of interrogating the proximity of a "new wave" of king culture to academic theory. Tracing the evolution of drag king performance in the Twin Cities from the 1996 workshop by Diane Torr to the formation of two distinct king troupes in the late 1990s demonstrates a particular trajectory in kinging that reflects a new consciousness and enactment of gender theory through artistic praxis. Participation plays a key role in breaking down the distance between spectator and performer in venues such as the First International Drag King Extravaganza in Columbus, Ohio, and Melinda Hubman's art installation "Performing Masculinities: Take a Chance on Gender" in Minneapolis. By engaging the "audience" in drag, the Extravaganza "Science Fair" successfully referenced drag kings' shared history with early American freak shows in a clever and critical way. Moving beyond the contest framework of early king shows, new drag king troupes like Minneapolis' Dykes Do Drag are "mixing it up" in an attempt to complicate notions of butch/femme gender roles, sexuality, and drag stereotypes.

  5. Estimating the sustainability of hubs

    NARCIS (Netherlands)

    Lieshout, R.; Zuidberg, J.; Veldhuis, J.

    2008-01-01

    Several airports in the world are or will be confronted with capacity problems in the near future. As a result of this congestion, many airports will face a selectivity problem: which traffic segments must be accommodated and which segments are less crucial? At hub airports there is generally one

  6. Beijing: Next International Financial Hub?

    Institute of Scientific and Technical Information of China (English)

    Li Zhen

    2008-01-01

    @@ Beijing's new financial dream On May 5,the Beijing Municipal Government released a notice regarding its plans to spur the financial industry,vowing to put forth a strong effort to become the national financial decision-making center,financial management center and financial information and services center,and formally announcing its ambitious aspiration to become a financial hub with international influence.

  7. PolarHub: A Global Hub for Polar Data Discovery

    Science.gov (United States)

    Li, W.

    2014-12-01

    This paper reports the outcome of a NSF project in developing a large-scale web crawler PolarHub to discover automatically the distributed polar dataset in the format of OGC web services (OWS) in the cyberspace. PolarHub is a machine robot; its goal is to visit as many webpages as possible to find those containing information about polar OWS, extract this information and store it into the backend data repository. This is a very challenging task given huge data volume of webpages on the Web. Three unique features was introduced in PolarHub to make it distinctive from earlier crawler solutions: (1) a multi-task, multi-user, multi-thread support to the crawling tasks; (2) an extensive use of thread pool and Data Access Object (DAO) design patterns to separate persistent data storage and business logic to achieve high extendibility of the crawler tool; (3) a pattern-matching based customizable crawling algorithm to support discovery of multi-type geospatial web services; and (4) a universal and portable client-server communication mechanism combining a server-push and client pull strategies for enhanced asynchronous processing. A series of experiments were conducted to identify the impact of crawling parameters to the overall system performance. The geographical distribution pattern of all PolarHub identified services is also demonstrated. We expect this work to make a major contribution to the field of geospatial information retrieval and geospatial interoperability, to bridge the gap between data provider and data consumer, and to accelerate polar science by enhancing the accessibility and reusability of adequate polar data.

  8. Drag on Sessile Drops

    Science.gov (United States)

    Milne, Andrew J. B.; Fleck, Brian; Nobes, David; Sen, Debjyoti; Amirfazli, Alidad; University of Alberta Mechanical Engineering Collaboration

    2013-11-01

    We present the first ever direct measurements of the coefficient of drag on sessile drops at Reynolds numbers from the creeping flow regime up to the point of incipient motion, made using a newly developed floating element differential drag sensor. Surfaces of different wettabilities (PMMA, Teflon, and a superhydrophobic surface (SHS)), wet by water, hexadecane, and various silicone oils, are used to study the effects of drop shape, and fluid properties on drag. The relation between drag coefficient and Reynolds number (scaled by drop height) varies slightly with liquid-solid system and drop volume with results suggesting the drop experiences increased drag compared to similar shaped solid bodies due to drop oscillation influencing the otherwise laminar flow. Drops adopting more spherical shapes are seen to experience the greatest force at any given airspeed. This indicates that the relative exposed areas of drops is an important consideration in terms of force, with implications for the shedding of drops in applications such as airfoil icing and fuel cell flooding. The measurement technique used in this work can be adapted to measure drag force on other deformable, lightly adhered objects such as dust, sand, snow, vesicles, foams, and biofilms. The authours acknowledge NSERC, Alberta Innovates Technology Futures, and the Killam Trusts.

  9. Book fair

    CERN Multimedia

    2006-01-01

    The Swiss academic publishing house 'Presses Polytechniques Universitaires Romandes'will be presenting its most recent scientific and technical publications at a book fair in the lobby of the Main Building (60) from 10 a.m. to 4 p.m. on Thursday 28 September 2006.

  10. Toward Fairness

    Institute of Scientific and Technical Information of China (English)

    CHEN RAN

    2010-01-01

    @@ How can countries ensure a fair business environment in the flee trade area (FTA) between China and the Association of Southeast Asian Nations (ASEAN)? The question triggered wide discussion among partici-pants at a forum on the China-ASEAN Free Trade Area (CAFTA) held on January 7-8 in Nanning, capital of southwest China's Guangxi Zhuang Autonomous Region.

  11. Fair Pi

    OpenAIRE

    2006-01-01

    International audience; In this paper, we define fair computations in the pi-calculus. We follow Costa and Stirling's approach for CCS-like languages but exploit a more natural labeling method of process actions to filter out unfair process executions. The new labeling allows us to prove all the significant properties of the original one, such as unicity, persistence and disappearance of labels. It also turns out that the labeled pi-calculus is a conservative extension of the standard one. We...

  12. The once & future repository, HKU's Scholars Hub

    OpenAIRE

    Palmer, DT; Castro, P.; Bollini, A; Mennielli, M

    2015-01-01

    The HKU Scholars Hub (the Hub) began service as a traditional institutional repository of The University of Hong Kong (HKU). However this format was not compelling to HKU researchers. Fortunately a subsequent reformation of the HKU statement on university mission and vision infused new life and purpose into the project. Over the next five years, in partnership with the Italian University Consortium, Cineca, the HKU Libraries transformed the Hub from an IR to a Current Research Information ...

  13. On GitHub's Programming Languages

    OpenAIRE

    2016-01-01

    GitHub is the most widely used social, distributed version control system. It has around 10 million registered users and hosts over 16 million public repositories. Its user base is also very active as GitHub ranks in the top 100 Alexa most popular websites. In this study, we collect GitHub's state in its entirety. Doing so, allows us to study new aspects of the ecosystem. Although GitHub is the home to millions of users and repositories, the analysis of users' activity time-series reveals tha...

  14. Planning a Science Fair

    Science.gov (United States)

    Ebert, Jim

    1976-01-01

    Presented are views, on planning science fairs and science fair projects, of a fair coordinator, a science teacher, and students. Also included are 25 questions which might result in science fair projects. (SL)

  15. Virtual Campus Hub technical evaluation report

    DEFF Research Database (Denmark)

    Vercoulen, Frank; Badger, Merete; Monaco, Lucio;

    This report describes and discusses the technical achievements of the Virtual Campus Hub project and formulates a brief agenda for the future.......This report describes and discusses the technical achievements of the Virtual Campus Hub project and formulates a brief agenda for the future....

  16. Logistics hubs: an integration of transport infrastructure

    CSIR Research Space (South Africa)

    Botha, M

    2008-07-01

    Full Text Available Logistics hubs are very well established internationally and many examples exist where these have been successfully built and implemented. This success have lead to the proliferation of such hubs and in South Africa there are many "decision makers...

  17. Hub discovery in partial correlation graphical models

    CERN Document Server

    Hero, Alfred

    2011-01-01

    This paper treats the problem of screening a p-variate sample for strongly and multiply connected vertices in the partial correlation graph associated with the the partial correlation matrix of the sample. This problem, called hub screening, is important in many applications ranging from network security to computational biology to finance to social networks. In the area of network security, a node that becomes a hub of high correlation with neighboring nodes might signal anomalous activity such as a coordinated flooding attack. In the area of computational biology the set of hubs of a gene expression correlation graph can serve as potential targets for drug treatment to block a pathway or modulate host response. In the area of finance a hub might indicate a vulnerable financial instrument or sector whose collapse might have major repercussions on the market. In the area of social networks a hub of observed interactions between criminal suspects could be an influential ringleader. The techniques and theory pr...

  18. Dynamic hubs show competitive and static hubs non-competitive regulation of their interaction partners.

    Directory of Open Access Journals (Sweden)

    Apurv Goel

    Full Text Available Date hub proteins have 1 or 2 interaction interfaces but many interaction partners. This raises the question of whether all partner proteins compete for the interaction interface of the hub or if the cell carefully regulates aspects of this process? Here, we have used real-time rendering of protein interaction networks to analyse the interactions of all the 1 or 2 interface hubs of Saccharomyces cerevisiae during the cell cycle. By integrating previously determined structural and gene expression data, and visually hiding the nodes (proteins and their edges (interactions during their troughs of expression, we predict when interactions of hubs and their partners are likely to exist. This revealed that 20 out of all 36 one- or two- interface hubs in the yeast interactome fell within two main groups. The first was dynamic hubs with static partners, which can be considered as 'competitive hubs'. Their interaction partners will compete for the interaction interface of the hub and the success of any interaction will be dictated by the kinetics of interaction (abundance and affinity and subcellular localisation. The second was static hubs with dynamic partners, which we term 'non-competitive hubs'. Regulatory mechanisms are finely tuned to lessen the presence and/or effects of competition between the interaction partners of the hub. It is possible that these regulatory processes may also be used by the cell for the regulation of other, non-cell cycle processes.

  19. Sphere Drag and Heat Transfer.

    Science.gov (United States)

    Duan, Zhipeng; He, Boshu; Duan, Yuanyuan

    2015-07-20

    Modelling fluid flows past a body is a general problem in science and engineering. Historical sphere drag and heat transfer data are critically examined. The appropriate drag coefficient is proposed to replace the inertia type definition proposed by Newton. It is found that the appropriate drag coefficient is a desirable dimensionless parameter to describe fluid flow physical behavior so that fluid flow problems can be solved in the simple and intuitive manner. The appropriate drag coefficient is presented graphically, and appears more general and reasonable to reflect the fluid flow physical behavior than the traditional century old drag coefficient diagram. Here we present drag and heat transfer experimental results which indicate that there exists a relationship in nature between the sphere drag and heat transfer. The role played by the heat flux has similar nature as the drag. The appropriate drag coefficient can be related to the Nusselt number. This finding opens new possibilities in predicting heat transfer characteristics by drag data. As heat transfer for flow over a body is inherently complex, the proposed simple means may provide an insight into the mechanism of heat transfer for flow past a body.

  20. Innovation Hub How-To

    DEFF Research Database (Denmark)

    Berger, Andreas; Brem, Alexander

    2016-01-01

    Firms around the world are eager to replicate the successes of enterprises that have established innovation labs in California's Silicon Valley. An analysis of four leading US companies that have set up idea incubators in the Valley—Xerox, Apple, Google, and Cisco—point to eight factors for succe...... disruptive over incremental innovation, and being patient. Regardless of where an innovation hub is established, the key to success lies in hiring creative, intrinsically motivated staff and then giving them the freedom to do what they do best.......Firms around the world are eager to replicate the successes of enterprises that have established innovation labs in California's Silicon Valley. An analysis of four leading US companies that have set up idea incubators in the Valley—Xerox, Apple, Google, and Cisco—point to eight factors for success...... in establishing an innovative environment: carefully considering the decision to set up such a center, hiring the right people, designing a framework for effective output, creating a buffer from bureaucratic distractions, securing a leader to champion the effort, focusing on business outcomes, fostering...

  1. Fair Preorder for Partial Fair Kripke Structures

    Institute of Scientific and Technical Information of China (English)

    徐蔚文; 陆鑫达

    2003-01-01

    This paper discussed how to handle the fairness conditions in partial Kripke structures. The partial Krip-ke structures were used for partial state spaces model checking, which is a new technique to solve problems of stateexplosion. This paper extended the partial Kripke structure with fairness conditions by defining a partial fair Krip-ke structure, and a 3-valued fair CTL(Computation-Tree Logic) semantics correspondingly. It defines a fair pre-order between partial Kripke structures that preserves fairness and is akin to fair bisimulation. In addition, a perti-nent theorem is also given, which indicates the relationship between the partial state spaces and the more completeone by illustrating the characterizations of states in the partial fair structure in terms of CTL formulae.

  2. Coulomb drag in quantum circuits

    OpenAIRE

    Levchenko, Alex; Kamenev, Alex

    2008-01-01

    We study drag effect in a system of two electrically isolated quantum point contacts (QPC), coupled by Coulomb interactions. Drag current exhibits maxima as a function of QPC gate voltages when the latter are tuned to the transitions between quantized conductance plateaus. In the linear regime this behavior is due to enhanced electron-hole asymmetry near an opening of a new conductance channel. In the non-linear regime the drag current is proportional to the shot noise of the driving circuit,...

  3. Zoning Districts - Volusia County HUB Zones

    Data.gov (United States)

    NSGIC Local Govt | GIS Inventory — Historically Underutilized Business (HUB) Zones in Volusia County. Go to http://www.sba.gov/hubzone or contact the Department of Economic Development (386) 248-8048...

  4. Motor coordination: a local hub for coordination.

    Science.gov (United States)

    Calabrese, Ronald L

    2014-03-31

    A local interneuron of a crayfish central pattern generator serves as a hub that integrates ascending and descending coordinating information and passes it on to a local oscillatory microcircuit to coordinate a series of segmental appendages known as swimmerets.

  5. An Alternative Science Fair.

    Science.gov (United States)

    Romjue, Mary Kalen; Clementson, John J.

    1992-01-01

    Proposes the organization of noncompetitive science fairs to create a more positive learning experience for children in the elementary grades. Describes methods of organizing and judging the fair, and provides a list of suggested resources for science fair projects. (MDH)

  6. Gravity Tunnel Drag

    CERN Document Server

    Concannon, Thomas

    2016-01-01

    The time it takes to fall down a tunnel through the center of the Earth to the other side takes approximately 42 minutes, but only when given several simplifying assumptions: a uniform density Earth; a gravitational field that varies linearly with radial position; a non-rotating Earth; a tunnel evacuated of air; and zero friction along the sides of the tunnel. Though several papers have singularly relaxed the first three assumptions, in this paper we relax the final two assumptions and analyze the motion of a body experiencing these types of drag forces in the tunnel. Under such drag forces, we calculate the motion of a transport vehicle through a tunnel of the Earth under uniform density, under constant gravitational acceleration, and finally under the more realistic Preliminary Reference Earth Model (PREM) density data. We find the density profile corresponding to a constant gravitational acceleration better models the motion through the tunnel compared to the PREM density profile, and the uniform density m...

  7. Validity and Fairness

    Science.gov (United States)

    Kane, Michael

    2010-01-01

    This paper presents the author's critique on Xiaoming Xi's article, "How do we go about investigating test fairness?," which lays out a broad framework for studying fairness as comparable validity across groups within the population of interest. Xi proposes to develop a fairness argument that would identify and evaluate potential fairness-based…

  8. Test Fairness: A Response

    Science.gov (United States)

    Davies, Alan

    2010-01-01

    This article presents the author's response to Xiaoming Xi's paper titled "How do we go about investigating test fairness?" In the paper, Xi offers "a means to fully integrate fairness investigations and practice". Given the current importance accorded to fairness in the language testing community, Xi makes a case for viewing fairness as an aspect…

  9. Contextual Hub Analysis Tool (CHAT): A Cytoscape app for identifying contextually relevant hubs in biological networks

    Science.gov (United States)

    Wiencko, Heather L.; Bernal-Llinares, Manuel; Bryan, Kenneth; Lynn, David J.

    2016-01-01

    Highly connected nodes (hubs) in biological networks are topologically important to the structure of the network and have also been shown to be preferentially associated with a range of phenotypes of interest. The relative importance of a hub node, however, can change depending on the biological context. Here, we report a Cytoscape app, the Contextual Hub Analysis Tool (CHAT), which enables users to easily construct and visualize a network of interactions from a gene or protein list of interest, integrate contextual information, such as gene expression or mass spectrometry data, and identify hub nodes that are more highly connected to contextual nodes (e.g. genes or proteins that are differentially expressed) than expected by chance. In a case study, we use CHAT to construct a network of genes that are differentially expressed in Dengue fever, a viral infection. CHAT was used to identify and compare contextual and degree-based hubs in this network. The top 20 degree-based hubs were enriched in pathways related to the cell cycle and cancer, which is likely due to the fact that proteins involved in these processes tend to be highly connected in general. In comparison, the top 20 contextual hubs were enriched in pathways commonly observed in a viral infection including pathways related to the immune response to viral infection. This analysis shows that such contextual hubs are considerably more biologically relevant than degree-based hubs and that analyses which rely on the identification of hubs solely based on their connectivity may be biased towards nodes that are highly connected in general rather than in the specific context of interest. Availability: CHAT is available for Cytoscape 3.0+ and can be installed via the Cytoscape App Store ( http://apps.cytoscape.org/apps/chat). PMID:27853512

  10. Contextual Hub Analysis Tool (CHAT): A Cytoscape app for identifying contextually relevant hubs in biological networks.

    Science.gov (United States)

    Muetze, Tanja; Goenawan, Ivan H; Wiencko, Heather L; Bernal-Llinares, Manuel; Bryan, Kenneth; Lynn, David J

    2016-01-01

    Highly connected nodes (hubs) in biological networks are topologically important to the structure of the network and have also been shown to be preferentially associated with a range of phenotypes of interest. The relative importance of a hub node, however, can change depending on the biological context. Here, we report a Cytoscape app, the Contextual Hub Analysis Tool (CHAT), which enables users to easily construct and visualize a network of interactions from a gene or protein list of interest, integrate contextual information, such as gene expression or mass spectrometry data, and identify hub nodes that are more highly connected to contextual nodes (e.g. genes or proteins that are differentially expressed) than expected by chance. In a case study, we use CHAT to construct a network of genes that are differentially expressed in Dengue fever, a viral infection. CHAT was used to identify and compare contextual and degree-based hubs in this network. The top 20 degree-based hubs were enriched in pathways related to the cell cycle and cancer, which is likely due to the fact that proteins involved in these processes tend to be highly connected in general. In comparison, the top 20 contextual hubs were enriched in pathways commonly observed in a viral infection including pathways related to the immune response to viral infection. This analysis shows that such contextual hubs are considerably more biologically relevant than degree-based hubs and that analyses which rely on the identification of hubs solely based on their connectivity may be biased towards nodes that are highly connected in general rather than in the specific context of interest.

  11. Collaborative Data Analytics with DataHub.

    Science.gov (United States)

    Bhardwaj, Anant; Karger, David; Subramanyam, Harihar; Deshpande, Amol; Madden, Sam; Wu, Eugene; Elmore, Aaron; Parameswaran, Aditya; Zhang, Rebecca

    2015-08-01

    While there have been many solutions proposed for storing and analyzing large volumes of data, all of these solutions have limited support for collaborative data analytics, especially given the many individuals and teams are simultaneously analyzing, modifying and exchanging datasets, employing a number of heterogeneous tools or languages for data analysis, and writing scripts to clean, preprocess, or query data. We demonstrate DataHub, a unified platform with the ability to load, store, query, collaboratively analyze, interactively visualize, interface with external applications, and share datasets. We will demonstrate the following aspects of the DataHub platform: (a) flexible data storage, sharing, and native versioning capabilities: multiple conference attendees can concurrently update the database and browse the different versions and inspect conflicts; (b) an app ecosystem that hosts apps for various data-processing activities: conference attendees will be able to effortlessly ingest, query, and visualize data using our existing apps; (c) thrift-based data serialization permits data analysis in any combination of 20+ languages, with DataHub as the common data store: conference attendees will be able to analyze datasets in R, Python, and Matlab, while the inputs and the results are still stored in DataHub. In particular, conference attendees will be able to use the DataHub notebook - an IPython-based notebook for analyzing data and storing the results of data analysis.

  12. Supervised hub-detection for brain connectivity

    Science.gov (United States)

    Kasenburg, Niklas; Liptrot, Matthew; Reislev, Nina Linde; Garde, Ellen; Nielsen, Mads; Feragen, Aasa

    2016-03-01

    A structural brain network consists of physical connections between brain regions. Brain network analysis aims to find features associated with a parameter of interest through supervised prediction models such as regression. Unsupervised preprocessing steps like clustering are often applied, but can smooth discriminative signals in the population, degrading predictive performance. We present a novel hub-detection optimized for supervised learning that both clusters network nodes based on population level variation in connectivity and also takes the learning problem into account. The found hubs are a low-dimensional representation of the network and are chosen based on predictive performance as features for a linear regression. We apply our method to the problem of finding age-related changes in structural connectivity. We compare our supervised hub-detection (SHD) to an unsupervised hub-detection and a linear regression using the original network connections as features. The results show that the SHD is able to retain regression performance, while still finding hubs that represent the underlying variation in the population. Although here we applied the SHD to brain networks, it can be applied to any network regression problem. Further development of the presented algorithm will be the extension to other predictive models such as classification or non-linear regression.

  13. Fair value accounting

    OpenAIRE

    Shamkuts, Volha, 1977-

    2010-01-01

    The thesis is devoted to fair value accounting. Fair value accounting implies that assets and liabilities get measured and reported in firm´s financial statements at their market value. The purpose of the thesis is to analyze the conceptual foundations of fair value accounting. The thesis is organized in the following way. First, origins and development of fair value accounting are discussed. Second, overview of fair value accounting is presented. The overview includes de...

  14. Java Fair Threads

    OpenAIRE

    Boussinot, Frédéric

    2001-01-01

    Fair threads are cooperative threads run by a fair scheduler which gives them equal access to the processor. Fair threads can communicate using broadcast events, and are fully portable as their semantics does not depends on the executing platform. Fine control over fair threads execution is possible allowing the programming of specific user-defined scheduling strategies. This paper presents fair threads in the context of the Java language, and describes the API to use them. Link with reactive...

  15. When superfluids are a drag

    Energy Technology Data Exchange (ETDEWEB)

    Roberts, David C [Los Alamos National Laboratory

    2008-01-01

    The article considers the dramatic phenomenon of seemingly frictionless flow of slow-moving superfluids. Specifically the question of whether an object in a superfluid flow experiences any drag force is addressed. A brief account is given of the history of this problem and it is argued that recent advances in ultracold atomic physics can shed much new light on this problem. The article presents the commonly held notion that sufficiently slow-moving superfluids can flow without drag and also discusses research suggesting that scattering quantum fluctuations might cause drag in a superfluid moving at any speed.

  16. Hub Status and Indexation of Container Ports

    Directory of Open Access Journals (Sweden)

    Yong-An Park

    2015-06-01

    This study develops two sub-indexes of port classification and capacity, and combines cases of these two sub-indexes into various types in order to find a proper port hub index. The paper demonstrates how different types of port hub index are useful measurements for evaluating outputs and inputs of container ports. In a case analysis we show that the indexes of period variables and lagged variables have more explanatory power with regard to changes of port throughputs and high correlation with inputs.

  17. Unsteady Velocity Measurements Taken Behind a Model Helicopter Rotor Hub in Forward Flight

    Science.gov (United States)

    Berry, John D.

    1997-01-01

    Drag caused by separated flow behind the hub of a helicopter has an adverse effect on aerodynamic performance of the aircraft. To determine the effect of separated flow on a configuration used extensively for helicopter aerodynamic investigations, an experiment was conducted using a laser velocimeter to measure velocities in the wake of a model helicopter hub operating at Mach-scaled conditions in forward flight. Velocity measurements were taken using a laser velocimeter with components in the vertical and downstream directions. Measurements were taken at 13 stations downstream from the rotor hub. At each station, measurements were taken in both a horizontal and vertical row of locations. These measurements were analyzed for harmonic content based on the rotor period of revolution. After accounting for these periodic velocities, the remaining unsteady velocities were treated as turbulence. Turbulence intensity distributions are presented. Average turbulent intensities ranged from approximately 2 percent of free stream to over 15 percent of free stream at specific locations and azimuths. The maximum average value of turbulence was located near the rear-facing region of the fuselage.

  18. Exploring hubness in Regional Trade Agreements

    NARCIS (Netherlands)

    Vaal, A. de

    2016-01-01

    In the plethora of Regional Trade Agreements (RTAs) some countries take in a more central position than others in the sense that some countries are much more engaged with other countries through RTAs. Furthermore, the position of some countries is that of a hub: they have (many) trade

  19. Hub location problems in transportation networks

    DEFF Research Database (Denmark)

    Gelareh, Shahin; Nickel, Stefan

    2011-01-01

    In this paper we propose a 4-index formulation for the uncapacitated multiple allocation hub location problem tailored for urban transport and liner shipping network design. This formulation is very tight and most of the tractable instances for MIP solvers are optimally solvable at the root node....... also introduce fixed cost values for Australian Post (AP) dataset....

  20. Optimising steel hub location in Thailand

    Directory of Open Access Journals (Sweden)

    Sakaradhorn Boontaveeyuwat

    2012-11-01

    Full Text Available The optimal location of a steel hub in Thailand was analysed by applying aspecific research methodology designed to evaluate locations near the seaports. The growth of Thailand’s steel industry has become a centre of attention in the last decade, resulting in substantial efforts to form a distribution service centre to minimise the logistic costs associated with handling large steel flows in the future. The main analysis of the steel hublocation focused on areas situated near Laem Cha Bang, Map Ta Phut and Prachuab ports since these top three ports are considered important in terms of their steel throughput in Thailand. The transport costs associated with the shipment and inland transport together with port tariffs were calculated for the proposed scenarios of steel hub establishment andthese were compared with the existing situation without steel hub. The findings showed that a steel hub located near Laem Cha Bang port was the optimal option involving a saving of 9.4% on the total system costs incurred under the existing situation.

  1. A State Cyber Hub Operations Framework

    Science.gov (United States)

    2016-06-01

    level cyber operations from state information technology (IT) and network infrastructure to hospitals , commercial banking, and manufacturing the...tools - TTPs necessary to operate and maintain Authoritative Data Repository for operational related artifacts . - Monitor and report on operations...development of Data Repository structures to enable storage of Cyber Hub related artifacts . - Provides Technical input to Business Case Analyses (BCAs

  2. Constructing Hongqiao Hub and Serving Regional Economy:Planning and Operation of Hongqiao Comprehensive Transportation Hub

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Taking Hongqiao Integrated Transportation Hub Project as a case, this paper introduces its origin, orientation, development programming, planning and design, road planning, information system planning, air-rail integrated transportation planning, disaster prevention planning, and so on.

  3. Over-heated Investment in Aluminum Hub Industry

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    <正>Aluminum hub is one of typical products with the comparative advantages.China’s aluminum hub industry is very competitive.In recent years,the value of export for the aluminum hub soared,increasing from USD130 millions in 1999 up to nearly USD1 billion in 2004.The main exporter are Wanfeng Auto Holding Group,Shanghai Fervent Alloy Wheel MFG Co.,Ltd.,Nanhai Zhongnan Aluminum Co., Ltd.,Taian Huatai Aluminum Hub Co.,Ltd.

  4. A Fair Proposition?

    Science.gov (United States)

    Grobman, Arnold

    1993-01-01

    Describes problems with school science fairs including poor judging and a lack of understanding by the students of their own projects. Suggests improvements to the system. One suggestion is for science fair projects to be displayed only in classrooms and not district or regional fairs. (PR)

  5. Resizing Triathlons for Fairness.

    Science.gov (United States)

    Wainer, Howard; De Veaux, Richard D.

    As currently configured, triathlons are dominated by cyclists and runners. The concept of fairness, as applied to triathlons, suggests that a cyclist, runner, and swimmer, all equally proficient, can each traverse the associated segment of the triathlon in approximately equal times. This definition of fairness is used to derive fair triathlon…

  6. Some Remarks on CFD Drag Prediction of an Aircraft Model

    Science.gov (United States)

    Peng, S. H.; Eliasson, P.

    Observed in CFD drag predictions for the DLR-F6 aircraft model with various configurations, some issues are addressed. The emphasis is placed on the effect of turbulence modeling and grid resolution. With several different turbulence models, the predicted flow feature around the aircraft is highlighted. It is shown that the prediction of the separation bubble in the wing-body junction is closely related to the inherent modeling mechanism of turbulence production. For the configuration with an additional fairing, which has effectively removed the separation bubble, it is illustrated that the drag prediction may be altered even for attached turbulent boundary layer when different turbulence models are used. Grid sensitivity studies are performed with two groups of subsequently refined grids. It is observed that, in contrast to the lift, the drag prediction is rather sensitive to the grid refinement, as well as to the artificial diffusion added for solving the turbulence transport equation. It is demonstrated that an effective grid refinement should drive the predicted drag components monotonically and linearly converged to a finite value.

  7. Southwest Regional Climate Hub and California Subsidiary Hub assessment of climate change vulnerability and adaptation and mitigation strategies

    Science.gov (United States)

    Emile Elias; Caiti Steele; Kris Havstad; Kerri Steenwerth; Jeanne Chambers; Helena Deswood; Amber Kerr; Albert Rango; Mark Schwartz; Peter Stine; Rachel Steele

    2015-01-01

    This report is a joint effort of the Southwest Regional Climate Hub and the California Subsidiary Hub (Sub Hub). The Southwest Regional Climate Hub covers Arizona, California, Hawai‘i and the U.S. affiliated Pacific Islands, Nevada, New Mexico, and Utah and contains vast areas of western rangeland, forests, and high-value specialty crops (Figure 1). The California Sub...

  8. Summary of Data from the First AIAA CFD Drag Prediction Workshop

    Science.gov (United States)

    Levy, David W.; Zickuhr, Tom; Vassberg, John; Agrawal, Shreekant; Wahls, Richard A.; Pirzadeh, Shahyar; Hemsch, Michael J.

    2002-01-01

    The results from the first AIAA CFD Drag Prediction Workshop are summarized. The workshop was designed specifically to assess the state-of-the-art of computational fluid dynamics methods for force and moment prediction. An impartial forum was provided to evaluate the effectiveness of existing computer codes and modeling techniques, and to identify areas needing additional research and development. The subject of the study was the DLR-F4 wing-body configuration, which is representative of transport aircraft designed for transonic flight. Specific test cases were required so that valid comparisons could be made. Optional test cases included constant-C(sub L) drag-rise predictions typically used in airplane design by industry. Results are compared to experimental data from three wind tunnel tests. A total of 18 international participants using 14 different codes submitted data to the workshop. No particular grid type or turbulence model was more accurate, when compared to each other, or to wind tunnel data. Most of the results overpredicted C(sub Lo) and C(sub Do), but induced drag (dC(sub D)/dC(sub L)(exp 2)) agreed fairly well. Drag rise at high Mach number was underpredicted, however, especially at high C(sub L). On average, the drag data were fairly accurate, but the scatter was greater than desired. The results show that well-validated Reynolds-Averaged Navier-Stokes CFD methods are sufficiently accurate to make design decisions based on predicted drag.

  9. Drag/thrust analysis of jet-propelled transonic transport aircraft; definition of physical drag components

    Energy Technology Data Exchange (ETDEWEB)

    Destarac, D. [Office National d' Etudes et de Recherches Aerospatiales (ONERA), 92 - Chatillon (France); Van der Vooren, J. [Senior research scientist, retired, Hoekse Waard (Netherlands)

    2004-09-01

    Drag/thrust analysis of jet-propelled transonic transport aircraft on the basis of calculated viscous flow is discussed. Unique definitions for viscous drag plus wave drag and for induced drag are established. The concept of additive through flow drag is introduced. Drag/thrust bookkeeping is given attention. All drag components can be calculated in the flow region adjacent to the aircraft, where numerical accuracy is expectingly highest. Uniform handling of complex aircraft configurations is brought within reach. Near-field/far-field drag balances are exact. Computational aspects are discussed, in particular the elimination of spurious drag sources. Numerical examples are given for a wing-body and for a wing-body-pylon-nacelle configuration. In either case, the spurious drag sources are eliminated. Acceptable agreement is obtained for the total drag in the first case, and for the installation drag in the second case. Extension of the analysis presented to propeller-driven transport aircraft is straightforward. (author)

  10. Extension of Goldstein's circulation function for optimal rotors with hub

    DEFF Research Database (Denmark)

    Okulov, Valery; Sørensen, Jens Nørkær; Shen, Wen Zhong

    2016-01-01

    The aerodynamic interaction or interference between rotor blades and hub body is usually very complicated, but some useful simplifications can be made by considering the hub with an infinite cylinder. Various attempts to find the optimum distribution of circulation by the lifting vortex lines...... method have been previously proposed to describe the blade interaction with the hub modeled by the infinite cylinder. In this case, the ideal distribution of bound circulation on the rotor blades is such that the shed vortex system in the hub-area is a set of helicoidal vortex sheets moving uniformly...... at the nose-area of the semi-infinite hub....

  11. Developmental Changes in Brain Network Hub Connectivity in Late Adolescence.

    Science.gov (United States)

    Baker, Simon T E; Lubman, Dan I; Yücel, Murat; Allen, Nicholas B; Whittle, Sarah; Fulcher, Ben D; Zalesky, Andrew; Fornito, Alex

    2015-06-17

    The human brain undergoes substantial development throughout adolescence and into early adulthood. This maturational process is thought to include the refinement of connectivity between putative connectivity hub regions of the brain, which collectively form a dense core that enhances the functional integration of anatomically distributed, and functionally specialized, neural systems. Here, we used longitudinal diffusion magnetic resonance imaging to characterize changes in connectivity between 80 cortical and subcortical anatomical regions over a 2 year period in 31 adolescents between the ages of 15 and 19 years. Connectome-wide analysis indicated that only a small subset of connections showed evidence of statistically significant developmental change over the study period, with 8% and 6% of connections demonstrating decreased and increased structural connectivity, respectively. Nonetheless, these connections linked 93% and 90% of the 80 regions, respectively, pointing to a selective, yet anatomically distributed pattern of developmental changes that involves most of the brain. Hub regions showed a distinct tendency to be highly connected to each other, indicating robust "rich-club" organization. Moreover, connectivity between hubs was disproportionately influenced by development, such that connectivity between subcortical hubs decreased over time, whereas frontal-subcortical and frontal-parietal hub-hub connectivity increased over time. These findings suggest that late adolescence is characterized by selective, yet significant remodeling of hub-hub connectivity, with the topological organization of hubs shifting emphasis from subcortical hubs in favor of an increasingly prominent role for frontal hub regions.

  12. Spatial Economic Hubs and State Power

    Institute of Scientific and Technical Information of China (English)

    Xuan Xingzhang; Huang Jing

    2008-01-01

    The paper seeks to analyze the rise of state power in the light of spatial economic shifts and examines the historical context of China's rise and challenges facing it. In world history, only countries that were spatial economic hubs have been able to enjoy prosperity over centuries. China is not yet such a country, despite its persistent efforts. Nor is China likely to become an economic hub in the foreseeable future. China is under mounting pressure from new economic demands posed by shifts in the geo-economic status of the U.S.. The fact that the global economy thrives along coastlines also causes problems for China, a country with a long coastline and a vast hinterland, creating rifts between northern and southern China, central and local governments, and different provinces. All these factors might well hinder China's development in the future.

  13. Fairness and nanotechnology concern.

    Science.gov (United States)

    McComas, Katherine A; Besley, John C

    2011-11-01

    Research suggests that fairness perceptions matter to people who are asked to evaluate the acceptability of risks or risk management. Two separate national random surveys (n = 305 and n = 529) addressed Americans' concerns about and acceptance of nanotechnology risk management in the context of the degree to which they view scientists and risk managers as fair. The first survey investigated general views about scientists across four proposed dimensions of fairness (distributional, procedural, interpersonal, and informational). The results show that respondents who believe that the outcomes of scientific research tend to result in unequal benefits (distributional fairness) and that the procedures meant to protect the public from scientific research are biased (procedural fairness) were more concerned about nanotechnology. Believing scientists would treat them with respect (interpersonal fairness) and ensure access to information (informational fairness) were not significant predictors of concern. The second study also looked at these four dimensions of fairness but focused on perceptions of risk managers working for government, universities, and major companies. In addition to concern, it also examined acceptance of nanotechnology risk management. Study 2 results were similar to those of study 1 for concern; however, only perceived informational fairness consistently predicted acceptance of nanotechnology risk management. Overall, the study points to the value of considering fairness perceptions in the study of public perceptions of nanotechnology. © 2011 Society for Risk Analysis.

  14. Topographic hub maps of the human structural neocortical network.

    Directory of Open Access Journals (Sweden)

    Emil H J Nijhuis

    Full Text Available Hubs within the neocortical structural network determined by graph theoretical analysis play a crucial role in brain function. We mapped neocortical hubs topographically, using a sample population of 63 young adults. Subjects were imaged with high resolution structural and diffusion weighted magnetic resonance imaging techniques. Multiple network configurations were then constructed per subject, using random parcellations to define the nodes and using fibre tractography to determine the connectivity between the nodes. The networks were analysed with graph theoretical measures. Our results give reference maps of hub distribution measured with betweenness centrality and node degree. The loci of the hubs correspond with key areas from known overlapping cognitive networks. Several hubs were asymmetrically organized across hemispheres. Furthermore, females have hubs with higher betweenness centrality and males have hubs with higher node degree. Female networks have higher small-world indices.

  15. Extension of Goldstein's circulation function for optimal rotors with hub

    Science.gov (United States)

    Okulov, V. L.; Sørensen, J. N.; Shen, W. Z.

    2016-09-01

    The aerodynamic interaction or interference between rotor blades and hub body is usually very complicated, but some useful simplifications can be made by considering the hub with an infinite cylinder. Various attempts to find the optimum distribution of circulation by the lifting vortex lines method have been previously proposed to describe the blade interaction with the hub modeled by the infinite cylinder. In this case, the ideal distribution of bound circulation on the rotor blades is such that the shed vortex system in the hub-area is a set of helicoidal vortex sheets moving uniformly as if rigid, exactly as in the case where there is no influence of the streamtube deformations by the central hub-body. In the present investigation, we consider a more specific problem of the rotor-hub interaction where the initial flow streamtubes and the rotor slipstream submitted strong deformations at the nose-area of the semi-infinite hub.

  16. Ranking hubs and authorities using matrix functions

    OpenAIRE

    2012-01-01

    The notions of subgraph centrality and communicability, based on the exponential of the adjacency matrix of the underlying graph, have been effectively used in the analysis of undirected networks. In this paper we propose an extension of these measures to directed networks, and we apply them to the problem of ranking hubs and authorities. The extension is achieved by bipartization, i.e., the directed network is mapped onto a bipartite undirected network with twice as many nodes in order to ob...

  17. Developing Istanbul into a Regional Business Hub

    Science.gov (United States)

    2004-12-01

    beds). Every year Istanbul hosts people from all around the world for international summits, conferences, film and music festivals and sports...Kong, Taiwan, Malaysia , Thailand, and the Philippines are positioning themselves to be logistics hubs. On the other hand, in Eastern Europe; Czech...close to nearby major markets of the world, are only some of Turkey’s many advantages. 2. Istanbul Throughout history , Istanbul has been a city at the

  18. Drag coefficient for the air-sea exchange in hurricane conditions

    CERN Document Server

    Golbraikh, E

    2013-01-01

    The physical model is proposed for prediction of the non-monotonic drag coefficient variation with the neutral stability 10-m wind speed, U10. The model is based upon measurements of the foam coverage fraction and characteristic size of foam bubbles with U10, and on the drag coefficient approximation by the linearly weighted averaging over alternating foam-free and foam-covered portions of the ocean surface. The obtained drag coefficient is in fair agreement with that obtained by field measurements of the vertical variation of mean wind speed in Powell et al. (Nature, 2003) which discover reduction of the sea-surface drag with U10 rising to hurricane conditions.

  19. Comparison of NTF Experimental Data with CFD Predictions from the Third AIAA CFD Drag Prediction Workshop

    Science.gov (United States)

    Vassberg, John C.; Tinoco, Edward N.; Mani, Mori; Levy, David; Zickuhr, Tom; Mavriplis, Dimitri J.; Wahls, Richard A.; Morrison, Joseph H.; Brodersen, Olaf P.; Eisfeld, Bernhard; Murayama, Mitsuhiro

    2008-01-01

    Recently acquired experimental data for the DLR-F6 wing-body transonic transport con figuration from the National Transonic Facility (NTF) are compared with the database of computational fluid dynamics (CFD) predictions generated for the Third AIAA CFD Drag Prediction Workshop (DPW-III). The NTF data were collected after the DPW-III, which was conducted with blind test cases. These data include both absolute drag levels and increments associated with this wing-body geometry. The baseline DLR-F6 wing-body geometry is also augmented with a side-of-body fairing which eliminates the flow separation in this juncture region. A comparison between computed and experimentally observed sizes of the side-of-body flow-separation bubble is included. The CFD results for the drag polars and separation bubble sizes are computed on grids which represent current engineering best practices for drag predictions. In addition to these data, a more rigorous attempt to predict absolute drag at the design point is provided. Here, a series of three grid densities are utilized to establish an asymptotic trend of computed drag with respect to grid convergence. This trend is then extrapolated to estimate a grid-converged absolute drag level.

  20. Aerodynamic Drag and Gyroscopic Stability

    CERN Document Server

    Courtney, Elya R

    2013-01-01

    This paper describes the effects on aerodynamic drag of rifle bullets as the gyroscopic stability is lowered from 1.3 to 1.0. It is well known that a bullet can tumble for stability less than 1.0. The Sierra Loading Manuals (4th and 5th Editions) have previously reported that ballistic coefficient decreases significantly as gyroscopic stability, Sg, is lowered below 1.3. These observations are further confirmed by the experiments reported here. Measured ballistic coefficients were compared with gyroscopic stabilities computed using the Miller Twist Rule for nearly solid metal bullets with uniform density and computed using the Courtney-Miller formula for plastic-tipped bullets. The experiments reported here also demonstrate a decrease in aerodynamic drag near Sg = 1.23 +/- 0.02. It is hypothesized that this decrease in drag over a narrow band of Sg values is due to a rapid damping of coning motions (precession and nutation). Observation of this drag decrease at a consistent value of Sg demonstrates the relati...

  1. Drag Reduction of Bacterial Cellulose Suspensions

    Directory of Open Access Journals (Sweden)

    Satoshi Ogata

    2011-01-01

    Full Text Available Drag reduction due to bacterial cellulose suspensions with small environmental loading was investigated. Experiments were carried out by measuring the pressure drop in pipe flow. It was found that bacterial cellulose suspensions give rise to drag reduction in the turbulent flow range. We observed a maximum drag reduction ratio of 11% and found that it increased with the concentration of the bacterial cellulose suspension. However, the drag reduction effect decreased in the presence of mechanical shear.

  2. Coulomb drag in the mesoscopic regime

    DEFF Research Database (Denmark)

    Mortensen, N.A.; Flensberg, Karsten; Jauho, Antti-Pekka

    2002-01-01

    We present a theory for Coulomb drag between two mesoscopic systems which expresses the drag in terms of scattering matrices and wave functions. The formalism can be applied to both ballistic and disordered systems and the consequences can be studied either by numerical simulations or analytic...... average drag for chaotic 2D-systems and dominating fluctuations of drag between quasi-ballistic wires with almost ideal transmission....

  3. It's Not Fair

    Science.gov (United States)

    Turner, Jane

    2012-01-01

    Is a "fair test" the only way to carry out science investigations? Many children (and primary teachers) following the National Curriculum in England and Wales would answer "yes" to this question. This is because fair test investigations have historically been promoted in national assessment, published curricula, schemes of work…

  4. Australianness as fairness

    DEFF Research Database (Denmark)

    Plage, Stefanie; Willing, Indigo; Skrbis, Zlatko

    2017-01-01

    such as fairness, openness and egalitarianism effectively enhances cosmopolitan outlooks. It identifies the mechanisms through which these same virtues are mobilized to rationalize the failure to actualize cosmopolitanism in everyday practice. We argue that Australianness understood as the popular ‘fair...

  5. It's Not Fair

    Science.gov (United States)

    Turner, Jane

    2012-01-01

    Is a "fair test" the only way to carry out science investigations? Many children (and primary teachers) following the National Curriculum in England and Wales would answer "yes" to this question. This is because fair test investigations have historically been promoted in national assessment, published curricula, schemes of work and assessment…

  6. Australianness as fairness

    DEFF Research Database (Denmark)

    Plage, Stefanie; Willing, Indigo; Skrbis, Zlatko

    2017-01-01

    such as fairness, openness and egalitarianism effectively enhances cosmopolitan outlooks. It identifies the mechanisms through which these same virtues are mobilized to rationalize the failure to actualize cosmopolitanism in everyday practice. We argue that Australianness understood as the popular ‘fair...

  7. Fairness and Ability Grouping.

    Science.gov (United States)

    Strike, Kenneth A.

    1983-01-01

    A recent controversy regarding ability grouping is that it is often perceived as a means whereby racial or class bias can be subtly transformed into mechanisms of discrimination which exhibit the appearance of fairness and objectivity. This article addresses the question of fairness in ability grouping. (CJB)

  8. Rethinking the Science Fair

    Science.gov (United States)

    Craven, John; Hogan, Tracy

    2008-01-01

    Spring is the season when thousands of creased cardboard pests can be found lodged under the armpits of students and teachers as they observe the educational rite of spring known as the school science fair. A recent visit to a local school's gymnasium to witness one of these events reminded the authors of why they so dislike science fairs. In this…

  9. It's Not Fair

    Science.gov (United States)

    Turner, Jane

    2012-01-01

    Is a "fair test" the only way to carry out science investigations? Many children (and primary teachers) following the National Curriculum in England and Wales would answer "yes" to this question. This is because fair test investigations have historically been promoted in national assessment, published curricula, schemes of work…

  10. Analytical calculation of the drag force near drag crisis of a falling sphere

    CERN Document Server

    Assis, Armando V D B; Branco, N S

    2010-01-01

    We obtain analitically the $v^2$ dependence of the drag force on a falling sphere close to the drag crisis, as well as the drag coefficient at the drag crisis, with excellent agreement with experiment. We take into account the effects of viscosity in creating a turbulent boundary layer and perform the calculations using the Navier-Stokes equation.

  11. Computational Fair Division

    DEFF Research Database (Denmark)

    Branzei, Simina

    Fair division is a fundamental problem in economic theory and one of the oldest questions faced through the history of human society. The high level scenario is that of several participants having to divide a collection of resources such that everyone is satisfied with their allocation -- e.g. two...... heirs dividing a car, house, and piece of land inherited. The literature on fair division was developed in the 20th century in mathematics and economics, but computational work on fair division is still sparse. This thesis can be seen as an excursion in computational fair division divided in two parts...... study alternative and richer models, such as externalities in cake cutting, simultaneous cake cutting, and envy-free cake cutting. The second part of the thesis tackles the fair allocation of multiple goods, divisible and indivisible. In the realm of divisible goods, we investigate the well known...

  12. Sperner's lemma and fair division

    OpenAIRE

    DAKSKOBLER, LARISA

    2016-01-01

    Fair division is an active research area in Mathematics, Economics, Computer Science, etc. There are many different kinds of fair division problems. These are often named after everyday situations: fair resource allocation, fair cake-cutting, fair chore division, room assignment – rent division, and more. Although many exact and approximative methods for finding fair solutions already exist, the area of fair division still expands and tries to find better solutions for everyday problems. The...

  13. 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)

  14. Supervised hub-detection for brain connectivity

    DEFF Research Database (Denmark)

    Kasenburg, Niklas; Liptrot, Matthew George; Reislev, Nina Linde

    2016-01-01

    A structural brain network consists of physical connections between brain regions. Brain network analysis aims to find features associated with a parameter of interest through supervised prediction models such as regression. Unsupervised preprocessing steps like clustering are often applied......-detection and a linear regression using the original network connections as features. The results show that the SHD is able to retain regression performance, while still finding hubs that represent the underlying variation in the population. Although here we applied the SHD to brain networks, it can be applied to any...

  15. Coulomb drag in coherent mesoscopic systems

    DEFF Research Database (Denmark)

    Mortensen, Niels Asger; Flensberg, Karsten; Jauho, Antti-Pekka

    2001-01-01

    , such as the random matrix theory, or by numerical simulations. We show that Coulomb drag is sensitive to localized states, which usual transport measurements do not probe. For chaotic 2D systems we find a vanishing average drag, with a nonzero variance. Disordered 1D wires show a finite drag, with a large variance......We present a theory for Coulomb drag between two mesoscopic systems. Our formalism expresses the drag in terms of scattering matrices and wave functions, and its range of validity covers both ballistic and disordered systems. The consequences can be worked out either by analytic means...

  16. Vapor layers reduce drag without the crisis

    Science.gov (United States)

    Vakarelski, Ivan; Berry, Joseph; Chan, Derek; Thoroddsen, Sigurdur

    2016-11-01

    The drag of a solid sphere moving in fluid is known to be only a function of the Reynolds number, Re and diminishes rapidly at the drag crisis around Re 3 ×105. A Leidenfrost vapor layer on a hot sphere surface can trigger the onset of the drag crisis at lower Re. By using a range of high viscosity perfluorocarbon liquids, we show that the drag reduction effect, can occur over a wide range of Re, from as low as 600. The Navier slip model with a viscosity dependent slip length captures the observed drag reduction and wake shape.

  17. An Introduction to Version Control Using GitHub Desktop

    Directory of Open Access Journals (Sweden)

    Daniel van Strien

    2016-06-01

    Full Text Available In this lesson you will be introduced to the basics of version control, understand why it is useful and implement basic version control for a plain text document using GitHub Desktop. By the end of this lesson you should understand: * what version control is and why it can be useful * the differences between Git and GitHub * how to implement version control using ‘GitHub Desktop,’ a Graphical User Interface for GitHub * be aware of other resources that will help you implement version control in your academic writing

  18. An Introduction to Version Control Using GitHub Desktop

    OpenAIRE

    Daniel van Strien

    2016-01-01

    In this lesson you will be introduced to the basics of version control, understand why it is useful and implement basic version control for a plain text document using GitHub Desktop. By the end of this lesson you should understand: * what version control is and why it can be useful * the differences between Git and GitHub * how to implement version control using ‘GitHub Desktop,’ a Graphical User Interface for GitHub * be aware of other resources that will help you imple...

  19. Turbulent drag reduction by polymers

    Energy Technology Data Exchange (ETDEWEB)

    Bonn, Daniel [Van der Waals-Zeeman Instituut, University of Amsterdam, Valckenierstraat 65 1018, XE Amsterdam (Netherlands); Amarouchene, Yacine [CPMOH, Universite Bordeaux 1, 351 Cours de la Liberation, 33405 Talence cedex (France); Wagner, Christian [Institut fuer Experimentalphysik, Universitaet des Saarlandes, Saarbruecken (Germany); Douady, Stephane [Laboratoire de Physique Statistique de l' ENS, 24 rue Lhomond, 75231 Paris cedex 05 (France); Cadot, Olivier [ENSTA, Chemin de la Huniere, 91761 Palaiseau cedex (France)

    2005-04-13

    The reduction of turbulent energy dissipation by addition of polymers is studied experimentally. We first address the question of where the action of the polymers is taking place. Subsequently, we show that there is a direct correlation of drag reduction with the elongational viscosity of the polymers. For this, the reduction of turbulent energy dissipation by addition of the biopolymer DNA is studied. These results open the way for a direct visualization study of the polymer conformation in a turbulent boundary layer.

  20. Drag Effects in Charm Photoproduction

    CERN Document Server

    Norrbin, E

    1999-01-01

    We have refined a model for charm fragmentation at hadron colliders. This model can also be applied to the photoproduction of charm. We investigate the effect of fragmentation on the distribution of produced charm quarks. The drag effect is seen to produce charm hadrons that are shifted in rapidity in the direction of the beam remnant. We also study the importance of different production mechanisms such as charm in the photon and from parton showers.

  1. Usable optimistic fair exchange

    OpenAIRE

    Küpçü, Alptekin; Lysyanskaya, A.

    2012-01-01

    Fairly exchanging digital content is an everyday problem. It has been shown that fair exchange cannot be achieved without a trusted third party (called the Arbiter). Yet, even with a trusted party, it is still non-trivial to come up with an efficient solution, especially one that can be used in a p2p file sharing system with a high volume of data exchanged. We provide an efficient optimistic fair exchange mechanism for bartering digital files, where receiving a payment in return for a file (b...

  2. Fairness is intuitive

    DEFF Research Database (Denmark)

    Cappelen, Alexander W.; Panton, Ulrik Haagen; Tungodden, Bertil

    2016-01-01

    In this paper we provide new evidence showing that fair behavior is intuitive to most people. We find a strong association between a short response time and fair behavior in the dictator game. This association is robust to controls that take account of the fact that response time might be affected...... by the decision-maker’s cognitive ability and swiftness. The experiment was conducted with a large and heterogeneous sample recruited from the general population in Denmark. We find a striking similarity in the association between response time and fair behavior across groups in the society, which suggests...

  3. Fairness is intuitive

    DEFF Research Database (Denmark)

    Cappelen, Alexander W.; Panton, Ulrik Haagen; Tungodden, Bertil

    2016-01-01

    In this paper we provide new evidence showing that fair behavior is intuitive to most people. We find a strong association between a short response time and fair behavior in the dictator game. This association is robust to controls that take account of the fact that response time might be affected...... by the decision-maker’s cognitive ability and swiftness. The experiment was conducted with a large and heterogeneous sample recruited from the general population in Denmark. We find a striking similarity in the association between response time and fair behavior across groups in the society, which suggests...

  4. Fairness in society

    CERN Document Server

    Flomenbom, Ophir

    2011-01-01

    Models that explain the economical and political realities of nowadays societies should help all the world's citizens. Yet, the last four years showed that the current models are missing. Here we develop a dynamical society-deciders model showing that the long lasting economical stress can be solved when increasing fairness in nations. fairness is computed for each nation using indicators from economy and politics. Rather than austerity versus spending, the dynamical model suggests that solving crises in western societies is possible with regulations that reduce the stability of the deciders, while shifting wealth in the direction of the people. This shall increase the dynamics among socio-economic classes, further increasing fairness.

  5. Physics at FAIR

    Energy Technology Data Exchange (ETDEWEB)

    Chattopadhyay, Subhasis

    2014-11-15

    The Facility for Antiproton and Ion Research (FAIR) is under construction at Darmstadt, Germany. It will deliver high intensity beams of ions and antiprotons for experiments in the fields of atomic physics, plasma physics, nuclear physics, hadron physics, nuclear matter physics, material physics and biophysics. One of the scientific pillars of FAIR is the Compressed Baryonic Matter (CBM) experiment which is designed for the study of high density nuclear matter as it exists in the core of neutron stars. In this article the scientific program of FAIR will be reviewed with emphasis on the CBM experiment.

  6. SHANGHAI INTERNATIONAL INDUSTRIAL FAIR

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    @@ Third Shanghai International Industrial Fair was held in New International Fair Center in Pudong Area in late November. This industrial fair titled "Information and Industrialization" aimed at highlighting China's high technology and industrial achievements in the new century. The sponsors for this session of industrial fair include China State Economic and Trade Commission, Ministry of Foreign Economic and Trade Relations, Ministry of Information Industry, Ministry of Science and Technology, Ministry of Education, Chinese Academy of Sciences and Shanghai Government.CNPC and Sinopec participated in the exhibition displaying a number of the latest technologies such as PetroChina's model for state land resources and Sinopec's model for 300,000-ton ethylene project.

  7. On fairness and randomness

    DEFF Research Database (Denmark)

    Jaeger, Manfred

    2009-01-01

    We investigate the relation between the behavior of non-deterministic systems under fairness constraints, and the behavior of probabilistic systems. To this end, first a framework based on computable stopping strategies is developed that provides a common foundation for describing both fair...... and probabilistic behavior. On the basis of stopping strategies it is then shown that fair behavior corresponds in a precise sense to random behavior in the sense of Martin-Löf's definition of randomness. We view probabilistic systems as concrete implementations of more abstract non-deterministic systems. Under...... this perspective the question is investigated what probabilistic properties are needed in such an implementation to guarantee (with probability one) certain required fairness properties in the behavior of the probabilistic system. Generalizing earlier concepts of ε -bounded transition probabilities, we introduce...

  8. Is Equality Fair?

    Directory of Open Access Journals (Sweden)

    Arthur Tarasov

    2015-11-01

    Full Text Available This paper attempts to answer the question whether people consider decisions that lead to equal outcomes fair. I find that this is not always the case. In an experiment where subjects are given equal opportunities to choose how to divide money between each other in a two-player game, any strategy is perceived to be fair more than half the time, including the profit-maximizing strategy. The equal divisions that lead to equal outcomes are sometimes considered unfair by both players. Moreover, players frequently punished the others, whose decisions led to equal outcomes. I hypothesize that such punishments occur because people have different conceptions of what a fair outcome and fair punishment are

  9. China Fairs & Expos

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    @@ Agriculture,Fishery,Animal Husbandry2010 China Husbandry and New Technology,New Product, New Equipment Promotion and Trade Fair Date: April 16-April 18, 2010 Frequency: Yearly Venue: Fujian Economic and Trade Exhibition

  10. China Fairs & Expos

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Commodity and Trade Fair Urnmqi Foreign Economic Relations and Trade Fair Date:September 1-September 5,2008 Venue:Xinjiang International Exhibition Center Sector:Exhibition of new products,new technology and new project,to negotiate on import & export trade and domestic commodity trade,etc Web:www.urmqifair.com Add:107,Xinhua South Road,Urumchi,China, 830049 Tel:86-991-2850497/2879890 Fax:86-991-2850497/2879890 E-mail:office@urumqifair.com

  11. Theme of Vanity Fair

    Institute of Scientific and Technical Information of China (English)

    祝荣玲

    2008-01-01

    1.1The Theme:A Novel without a Hero There is one clear,overarching theme in Vanity Fair:A Novel without a Hero,and Thackeray telegraphs it in his title and subtitle.In the pages of Vanity Fair,all is vanity and all are vain.Some are more vain-more obsessed with self and with the ephemeral treasures of social position and money-than others,

  12. Liner Shipping Hub Network Design in a Competitive Environment

    DEFF Research Database (Denmark)

    Gelareh, Shahin; Nickel, Stefan; Pisinger, David

    A new mixed integer programming formulation is proposed for hub-and-spoke network design in a competitive environment. It addresses competition between a newcomer liner service provider and an alliance, both operating on hub-and-spoke networks. The newcomer company maximizes its market share...

  13. Liner shipping hub network design in a competitive environment

    DEFF Research Database (Denmark)

    Gelareh, Shahin; Nickel, Stefan; Pisinger, David

    2010-01-01

    A mixed integer programming formulation is proposed for hub-and-spoke network design in a competitive environment. It addresses the competition between a newcomer liner service provider and an existing dominating operator, both operating on hub-and-spoke networks. The newcomer company maximizes its...

  14. International Education Hubs: Collaboration for Competitiveness and Sustainability

    Science.gov (United States)

    Knight, Jane

    2014-01-01

    This chapter focuses on the development of education hubs, a recent phenomenon in international higher education. Three models of hubs are examined in relation to the forces, risks, and opportunities of globalization and how local and international collaborations are essential for both global competitiveness and sustainability.

  15. Soft Power and Cultural Diplomacy: Emerging Education Hubs in Asia

    Science.gov (United States)

    Lee, Jack T.

    2015-01-01

    Several education hubs have emerged in Asia and the Middle East in recent years with a specific focus on cross-border higher education. Through considerable efforts in policy planning and generous funding, these hubs aim to transform a country or city into an eminent destination for education, research, and training. The inherent design of these…

  16. Optimal Model and Solution of Railway Hub Shift Working Plan

    Institute of Scientific and Technical Information of China (English)

    He Shiwei; Zhu Songnian; Lin Boliang

    1996-01-01

    Aiming at decreasing the hub transportation costs, a railway hub shift working plan in terms of multicommodity network flow model is set up for considering the coordination of freight working, train working and locomotive working plans. The solution and the calculating results are also introduced.

  17. Phased arrays: inline flow line hub inspection using phased arrays

    NARCIS (Netherlands)

    Bloom, J.G.P.; Chougrani, K.; Rundberg, H.; Oldenziel, G.; Deleye, X.; Martina, Q.

    2011-01-01

    The feasibility of the inspection of flow line hubs using the phased array technique was investigated to determine the surface area of the seal area degraded by corrosion. A clean model of the hub was simulated to gain insight into the geometrical echoes and to determine the area covered by the ultr

  18. A versatile framework for cooperative hub network development

    NARCIS (Netherlands)

    Cruijssen, F.C.A.M.; Borm, P.; Dullaert, W.; Hamers, H.

    2010-01-01

    This paper introduces a framework for cooperative hub network development. Building a joint physical hub for the transshipment of goods is expensive and, therefore, involves considerable risks for cooperating companies. In a practical setting, it is unlikely that an entire network will be built at o

  19. Education Hubs: A Fad, a Brand, an Innovation?

    Science.gov (United States)

    Knight, Jane

    2011-01-01

    The last decade has seen significant changes in all aspects of internationalization but most dramatically in the area of education and research moving across national borders. The most recent developments are education hubs. The term "education hub" is being used by countries who are trying to build a critical mass of local and foreign…

  20. Soft Power and Cultural Diplomacy: Emerging Education Hubs in Asia

    Science.gov (United States)

    Lee, Jack T.

    2015-01-01

    Several education hubs have emerged in Asia and the Middle East in recent years with a specific focus on cross-border higher education. Through considerable efforts in policy planning and generous funding, these hubs aim to transform a country or city into an eminent destination for education, research, and training. The inherent design of these…

  1. Climate programs update: USDA Southwest Regional Climate Hub update

    Science.gov (United States)

    PROGRAM OVERVIEW: The overarching goal of the USDA SW Climate Hub is to assist farmers, ranchers and foresters in addressing the effects of climate change including prolonged drought, increased insect outbreaks and severe wildfires. In the first year of operations, the SW Climate Hub (est. Februa...

  2. Liner shipping hub network design in a competitive environment

    DEFF Research Database (Denmark)

    Gelareh, Shahin; Nickel, Stefan; Pisinger, David

    2010-01-01

    A mixed integer programming formulation is proposed for hub-and-spoke network design in a competitive environment. It addresses the competition between a newcomer liner service provider and an existing dominating operator, both operating on hub-and-spoke networks. The newcomer company maximizes i...

  3. International Education Hubs: Collaboration for Competitiveness and Sustainability

    Science.gov (United States)

    Knight, Jane

    2014-01-01

    This chapter focuses on the development of education hubs, a recent phenomenon in international higher education. Three models of hubs are examined in relation to the forces, risks, and opportunities of globalization and how local and international collaborations are essential for both global competitiveness and sustainability.

  4. The 4 Pi Sky Transient Alerts Hub

    CERN Document Server

    Staley, Tim D

    2016-01-01

    We introduce the 4 Pi Sky 'hub', a collection of open data-services and underlying software packages built for rapid, fully automated reporting and response to astronomical transient alerts. These packages build on the mature 'VOEvent' standardized message-format, and aim to provide a decentralized and open infrastructure for handling transient alerts. In particular we draw attention to the initial release of voeventdb, an archive and remote-query service that allows astronomers to make historical queries about transient alerts. By employing spatial filters and web-of-citation lookups, voeventdb enables cross-matching of transient alerts to bring together data from multiple sources, as well as providing a point of reference when planning new follow-up campaigns. We also highlight the recent addition of optical-transient feeds from the ASASSN and GAIA projects to our VOEvent distribution stream. Both the source-code and deployment-scripts which implement these services are freely available and permissively lic...

  5. On the Predictability of Hub Height Winds

    DEFF Research Database (Denmark)

    Draxl, Caroline

    Wind energy is a major source of power in over 70 countries across the world, and the worldwide share of wind energy in electricity consumption is growing. The introduction of signicant amounts of wind energy into power systems makes accurate wind forecasting a crucial element of modern electrical...... grids. These systems require forecasts with temporal scales of tens of minutes to a few days in advance at wind farm locations. Traditionally these forecasts predict the wind at turbine hub heights; this information is then converted by transmission system operators and energy companies into predictions...... of power output at wind farms. Since the power available in the wind is proportional to the wind speed cubed, even small wind forecast errors result in large power prediction errors. Accurate wind forecasts are worth billions of dollars annually; forecast improvements will result in reduced costs...

  6. Location of Urban Logistic Terminals as Hub Location Problem

    Directory of Open Access Journals (Sweden)

    Jasmina Pašagić Škrinjar

    2012-09-01

    Full Text Available In this paper the problems of locating urban logistic terminals are studied as hub location problems that due to a large number of potential nodes in big cities belong to hard non-polynomial problems, the so-called NP-problems. The hub location problems have found wide application in physical planning of transport and telecommunication systems, especially systems of fast delivery, networks of logistic and distribution centres and cargo traffic terminals of the big cities, etc. The paper defines single and multiple allocations and studies the numerical examples. The capacitated single allocation hub location problems have been studied, with the provision of a mathematical model of selecting the location for the hubs on the network. The paper also presents the differences in the possibilities of implementing the exact and heuristic methods to solve the actual location problems of big dimensions i.e. hub problems of the big cities.

  7. Hub exchange operations in intermodal hub-and spoke networks : a performance comparison of rail-rail exchange facilities

    NARCIS (Netherlands)

    Bontekoning, Y.M.

    2006-01-01

    The implementation of hub-and-spoke networks in intermodal transport is suggested as one of the potential solutions for helping to increase the intermodal market share. Traditionally, trains are shunted at hubs; this is a time-consuming process. Since the early 1990s a new type of intermodal termina

  8. FAIR project at GSI

    Science.gov (United States)

    Kester, Oliver; Spiller, Peter; Stoecker, Horst

    FAIR -- the Facility for Antiproton and Ion Research in Europe -- constructed at GSI Helmholtzzentrum für Schwerionenforschung GmbH in Darmstadt comprises an international centre of heavy ion accelerators that will drive heavy ion and antimatter research (FBTR, 2006). FAIR will provide worldwide unique accelerator and experimental facilities allowing a large variety of fore-front research in physics and applied science. FAIR will deliver antiproton and ion beams of unprecedented intensities and qualities. The main part of the FAIR facility is a sophisticated and cost efficient accelerator system, which delivers parallel beams to different experiments of the FAIR experimental collaborations -- APPA, NuSTAR, CBM and PANDA. The accelerated primary beams will then be employed to create new, often highly exotic particles in a series of parallel experimental programs. Experiments with exotic particles will explore fundamental processes which are expected to have taken place in the early phases and still happen in the on-going evolution of the Universe. These processes produced the basic constituents of matter and overall structure we observe today...

  9. Coulomb drag in the mesoscopic regime

    DEFF Research Database (Denmark)

    Mortensen, N. Asger; Flensberg, Karsten; Jauho, Antti-Pekka

    2002-01-01

    We present a theory for Coulomb drug between two mesoscopic systems which expresses the drag in terms of scattering matrices and wave functions. The formalism can be applied to both ballistic and disordered systems and the consequences can be studied either by numerical simulations or analytic...... average drag for chaotic 2D-systems and dominating fluctuations of drag between quasi-ballistic wires with almost ideal transmission....

  10. Transformance: reading the gospel in drag.

    Science.gov (United States)

    McCune, Jeffrey Q

    2004-01-01

    Despite the large body of scholarship on drag and its performance of misogyny, mimicry, and masculinity, little attention has been paid to the role of musical genres in Black drag performance and its reception. This essay explores drag performances of gospel music and its relationship with the spectator at the Biology Bar, a Black gay drag site in Chicago. By examining the shift from the club "space" to the church "place," this research locates several possibilities for queer gospel performances. Through the introduction of a theory of transformance, this essay highlights the contradictions, complications, and complexities of the relationship between the Black church and the Black gay community.

  11. DOE Project on Heavy Vehicle Aerodynamic Drag

    Energy Technology Data Exchange (ETDEWEB)

    McCallen, R; Salari, K; Ortega, J; Castellucci, P; Pointer, D; Browand, F; Ross, J; Storms, B

    2007-01-04

    Class 8 tractor-trailers consume 11-12% of the total US petroleum use. At highway speeds, 65% of the energy expenditure for a Class 8 truck is in overcoming aerodynamic drag. The project objective is to improve fuel economy of Class 8 tractor-trailers by providing guidance on methods of reducing drag by at least 25%. A 25% reduction in drag would present a 12% improvement in fuel economy at highway speeds, equivalent to about 130 midsize tanker ships per year. Specific goals include: (1) Provide guidance to industry in the reduction of aerodynamic drag of heavy truck vehicles; (2) Develop innovative drag reducing concepts that are operationally and economically sound; and (3) Establish a database of experimental, computational, and conceptual design information, and demonstrate the potential of new drag-reduction devices. The studies described herein provide a demonstration of the applicability of the experience developed in the analysis of the standard configuration of the Generic Conventional Model. The modeling practices and procedures developed in prior efforts have been applied directly to the assessment of new configurations including a variety of geometric modifications and add-on devices. Application to the low-drag 'GTS' configuration of the GCM has confirmed that the error in predicted drag coefficients increases as the relative contribution of the base drag resulting from the vehicle wake to the total drag increases and it is recommended that more advanced turbulence modeling strategies be applied under those circumstances. Application to a commercially-developed boat tail device has confirmed that this restriction does not apply to geometries where the relative contribution of the base drag to the total drag is reduced by modifying the geometry in that region. Application to a modified GCM geometry with an open grille and radiator has confirmed that the underbody flow, while important for underhood cooling, has little impact on the drag

  12. Extensibility enables locomotion under isotropic drag

    CERN Document Server

    Pak, On Shun

    2011-01-01

    Anisotropic viscous drag is usually believed to be a requirement for the low Reynolds number locomotion of slender bodies such as flagella and cilia. Here we show that locomotion under isotropic drag is possible for extensible slender bodies. After general considerations, a two-ring swimmer and a model dinoflagellate flagellum are studied analytically to illustrate how extensibility can be exploited for self-propulsion without drag anisotropy. This new degree of freedom could be useful for some complex swimmer geometries and locomotion in complex fluid environments where drag anisotropy is weak or even absent.

  13. Coulomb drag in coherent mesoscopic systems

    DEFF Research Database (Denmark)

    Mortensen, Asger; Flensberg, Karsten; Jauho, Antti-Pekka

    2001-01-01

    We present a theory for Coulomb drag between two mesoscopic systems. Our formalism expresses the drag in terms of scattering matrices and wave functions, and its range of validity covers both ballistic and disordered systems. The consequences can be worked out either by analytic means, such as th......We present a theory for Coulomb drag between two mesoscopic systems. Our formalism expresses the drag in terms of scattering matrices and wave functions, and its range of validity covers both ballistic and disordered systems. The consequences can be worked out either by analytic means...

  14. Dalian International Garment Fair

    Institute of Scientific and Technical Information of China (English)

    Bai Yifeng

    2004-01-01

    @@ The 17th Dalian International Garment Fair is a new starting point. In the face of the main development trend of international and domes tic convention and exhibition industry, the fierce competition among the domestic exhibition industry, Dalian International Garment Fair sizes up the situation and the golden opportunity that China will revitalize the Northeast old industrial base and turn Dalian into the international shipping center in Northeast Asia; it takes the new Dalian Convention and Exhibition Center as a turning point. Under the leadership of Dalian Mu-nicipal Party Committee and Dalian municipal government, and under the support and assistance of the sponsors, Dalian International Garment Fair emancipates the mind and plans the future with the viewpoint of scientific development, innovative thinking and practical operation.

  15. Improvements of evaporation drag model

    Institute of Scientific and Technical Information of China (English)

    LI Xiao-Yan; XU Ji-Jun

    2004-01-01

    A special visible experiment facility has been designed and built, and an observable experiment is performed by pouring one or several high-temperature particles into a water pool in the facility. The experiment result has verified Yang's evaporation drag model, which holds that the non-symmetric profile of the local evaporation rate and the local density of vapor would bring about a resultant force on the hot particle so as to resist its motion. However, in Yang's evaporation drag model, radiation heat transfer is taken as the only way to transfer heat from hot particle to the vapor-liquid interface, and all of the radiation energy is deposited on the vapor-liquid interface and contributed to the vaporization rate and mass balance of the vapor film. In improved model heat conduction and heat convection are taken into account. This paper presents calculations of the improved model, putting emphasis on the effect of hot particle's temperature on the radiation absorption behavior of water.

  16. Fairness in Combinatorial Auctioning Systems

    CERN Document Server

    Saini, Megha

    2008-01-01

    One of the Multi-Agent Systems that is widely used by various government agencies, buyers and sellers in a market economy, in such a manner so as to attain optimized resource allocation, is the Combinatorial Auctioning System (CAS). We study another important aspect of resource allocations in CAS, namely fairness. We present two important notions of fairness in CAS, extended fairness and basic fairness. We give an algorithm that works by incorporating a metric to ensure fairness in a CAS that uses the Vickrey-Clark-Groves (VCG) mechanism, and uses an algorithm of Sandholm to achieve optimality. Mathematical formulations are given to represent measures of extended fairness and basic fairness.

  17. Observations from varying the lift and drag inputs to a noise prediction method for supersonic helical tip speed propellers

    Science.gov (United States)

    Dittmar, J. H.

    1984-01-01

    Previous comparisons between calculated and measured supersonic helical tip speed propeller noise show them to have different trends of peak blade passing tone versus helical tip Mach number. It was postulated that improvements in this comparison could be made first by including the drag force terms in the prediction and then by reducing the blade lift terms at the tip to allow the drag forces to dominate the noise prediction. Propeller hub to tip lift distributions were varied, but they did not yield sufficient change in the predicted lift noise to improve the comparison. This result indicates that some basic changes in the theory may be needed. In addition, the noise predicted by the drag forces did not exhibit the same curve shape as the measured data. So even if the drag force terms were to dominate, the trends with helical tip Mach number for theory and experiment would still not be the same. The effect of the blade shock wave pressure rise was approxmated by increasing the drag coefficient at the blade tip. Predictions using this shock wdave approximation did have a curve shape similar to the measured data. This result indicates that the shock pressure rise probably controls the noise at supersonic tip speed and that the linear prediction method can give the proper noise trend with Mach number.

  18. Flow Merging and Hub Route Optimization in Collaborative Transportation

    Directory of Open Access Journals (Sweden)

    Kerui Weng

    2014-01-01

    Full Text Available This paper studies the optimal hub routing problem of merged tasks in collaborative transportation. This problem allows all carriers’ transportation tasks to reach the destinations optionally passing through 0, 1, or 2 hubs within limited distance, while a cost discount on arcs in the hub route could be acquired after paying fixed charges. The problem arises in the application of logistics, postal services, airline transportation, and so forth. We formulate the problem as a mixed-integer programming model, and provide two heuristic approaches, respectively, based on Lagrangian relaxation and Benders decomposition. Computational experiments show that the algorithms work well.

  19. GitHub open source project recommendation system

    OpenAIRE

    Matek, Tadej; Zebec, Svit Timej

    2016-01-01

    Hosting platforms for software projects can form collaborative social networks and a prime example of this is GitHub which is arguably the most popular platform of this kind. An open source project recommendation system could be a major feature for a platform like GitHub, enabling its users to find relevant projects in a fast and simple manner. We perform network analysis on a constructed graph based on GitHub data and present a recommendation system that uses link prediction.

  20. The Opportunities and Threats of Turning Airports into Hubs

    Science.gov (United States)

    Kraus, Andreas; Koch, Benjamin

    2006-01-01

    This paper examines the opportunities and threats which arise when turning origin/destination airports into hubs. The analysis focuses on market development trends, competitive structures, especially in the light of airline network strategies and the growing rivalry between airports, and finally the potential financial impacts for the airport, including both investment efforts and the financial results from hub operations. We argue that in most cases a decision against converting a traditional origin/destination airport into a major transfer point is preferable to the transformation into a hub.

  1. Fair Factory Floors

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The number of labor disputes has soared and fairness remains elusive China’s Labor Contract Law, which has been in effect since January 1, 2008, has had significant positive impacts on the labor market, but there are still many difficulties facing workers and employers. In April 2009, Beijing’s Transition Institute conducted labor research in textile

  2. Fair mulighedslighed og sundhed

    DEFF Research Database (Denmark)

    Nielsen, Lasse

    2014-01-01

    Når vi skal diskutere de normative spørgsmål, der rejser sig i forbindelse med ulighed i sundhed, er Norman Daniels’ teori om retfærdig sundhed central. Teoriens omdrejningspunkt er en udvidelse af Rawls’ princip om fair mulighedslighed til også at omfatte sundhed, og den er uden tvivl blandt de...

  3. A Fair Production

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Traditional markets are returning to big cities in China,but with a new twist:They’re organic AFTER participating in Beijing’s"Country Fair"in March,a netizen going by the name"north slope"wrote in his blog,"It’s more like a creative market.

  4. Fair mulighedslighed og sundhed

    DEFF Research Database (Denmark)

    Nielsen, Lasse

    2014-01-01

    Når vi skal diskutere de normative spørgsmål, der rejser sig i forbindelse med ulighed i sundhed, er Norman Daniels’ teori om retfærdig sundhed central. Teoriens omdrejningspunkt er en udvidelse af Rawls’ princip om fair mulighedslighed til også at omfatte sundhed, og den er uden tvivl blandt de...

  5. Contract law as fairness

    NARCIS (Netherlands)

    J. Klijnsma

    2015-01-01

    This article examines the implications for contract law of Rawls' theory of justice as fairness. It argues that contract law as an institution is part of the basic structure of society and as such subject to the principles of justice. Discussing the basic structure in relation to contract law is par

  6. Super Science Fair Sourcebook.

    Science.gov (United States)

    Iritz, Maxine Haren

    This guide to science fair projects is designed for students and provides clear directions on how to complete a successful science project. Real projects are used as examples and information and advice is provided by teachers, judges, and participants and their families about the process. Topics covered in this book include choosing a science fair…

  7. China Fairs & Expos

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Food and Additives, Beverage, Drinks, Seasonings, Dairy Products Hong Kong International Tea Fair Date: August 12-August 15, 2011 Venue: Hong Kong Convention and Exhibition Center Exhibits: Tea, processing equipment and testing services, tea ware, tea bars/organizations, tea technology, tea service and publications.

  8. The Madam Fair

    Institute of Scientific and Technical Information of China (English)

    1997-01-01

    "NADAM" means "entertainment" or "game" in Mongolian. The Nadam Fair, a traditional Mongolian gathering, is held each year in summer or autumn and features horse racing, wrestling, shooting, singing and dancing. In the summer, I, together with my friends, traveled to Dong Ujimqin Banner of Xilin Gol League in Inner Mongolia for

  9. Drag Coefficient of Thin Flexible Cylinder

    Science.gov (United States)

    Subramanian, Chelakara; Gurram, Harika

    2015-11-01

    Measurements of drag coefficients of thin flexible cylindrical wires are described for the Reynolds number range between 250 - 1000. Results indicate that the coefficient values are about 20 to 30 percent lower than the reported laminar flow values for rigid cylinders. Possible fluid dynamics mechanism causing the reduction in drag will be discussed.

  10. Determination of the surface drag coefficient

    DEFF Research Database (Denmark)

    Mahrt, L.; Vickers, D.; Sun, J.L.

    2001-01-01

    This study examines the dependence of the surface drag coefficient on stability, wind speed, mesoscale modulation of the turbulent flux and method of calculation of the drag coefficient. Data sets over grassland, sparse grass, heather and two forest sites are analyzed. For significantly unstable ...

  11. Polymer flexibility and turbulent drag reduction

    NARCIS (Netherlands)

    Gillissen, J.J.J.

    2008-01-01

    Polymer-induced drag reduction is the phenomenon by which the friction factor of a turbulent flow is reduced by the addition of small amounts of high-molecular-weight linear polymers, which conformation in solution at rest can vary between randomly coiled and rodlike. It is well known that drag redu

  12. DRAG ON SUBMICRON NANOPARTICLE AGGREGATES

    Institute of Scientific and Technical Information of China (English)

    F.; Einar; Kruis

    2005-01-01

    A new procedure was developed for estimating the effective collision diameter of an aggregate composed of primary particles of any size. The coagulation coefficient of two oppositely charged particles was measured experimentally and compared with classic Fuchs theory, including a new method to account for particle non-sphericity. A second set of experiments were performed on well-defined nanoparticle aggregates at different stages of sintering, i.e. from the aggregate to the fully sintered stage. Here, electrical mobility was used to characterize the particle drag. The aggregates are being built from two different size-fractionated nanoparticle aerosols, the non-aggregated particles are discarded by an electrofilter and then they are passed through a furnace at concentrations low enough not to induce coagulation.

  13. A Hedonism Hub in the Human Brain

    Science.gov (United States)

    Zacharopoulos, G.; Lancaster, T. M.; Bracht, T.; Ihssen, N.; Maio, G. R.; Linden, D. E. J.

    2016-01-01

    Human values are abstract ideals that motivate behavior. The motivational nature of human values raises the possibility that they might be underpinned by brain structures that are particularly involved in motivated behavior and reward processing. We hypothesized that variation in subcortical hubs of the reward system and their main connecting pathway, the superolateral medial forebrain bundle (slMFB) is associated with individual value orientation. We conducted Pearson's correlation between the scores of 10 human values and the volumes of 14 subcortical structures and microstructural properties of the medial forebrain bundle in a sample of 87 participants, correcting for multiple comparisons (i.e.,190). We found a positive association between the value that people attach to hedonism and the volume of the left globus pallidus (GP).We then tested whether microstructural parameters (i.e., fractional anisotropy and myelin volume fraction) of the slMFB, which connects with the GP, are also associated to hedonism and found a significant, albeit in an uncorrected level, positive association between the myelin volume fraction within the left slMFB and hedonism scores. This is the first study to elucidate the relationship between the importance people attach to the human value of hedonism and structural variation in reward-related subcortical brain regions. PMID:27473322

  14. Ultrafast photon drag detector for intersubband spectroscopy

    Science.gov (United States)

    Sigg, Hans; Graf, Stephan; Kwakernaak, Martin H.; Margotte, Bernd; Erni, Daniel; Van Son, Peter; Köhler, Klaus

    1996-03-01

    The photon drag effect of a 2D electron gas is measured using the ps infrared pulses of the wavelength-tunable free electron laser source FELIX. The pulsed photon drag response is found to depend critically on the coupling characteristics of the electrical circuit. We therefore developed an impedance and velocity matched photon drag detector. It consists of a GaAs/AlGaAs multi quantum well sample which forms an integral part of a microstrip line. A Ge-prism enables incoupling at the critical total reflection angle. This novel transmission line integrated photon drag detector (TIP-detector) generates signal transients below 10 ps rise and fall times. Its continuous spectral response through the intersubband resonance is investigated at room temperature and at T=100 K. An analysis of the spectral lineshape of the photon drag current response yields information about the momentum relaxation times of the electrons in the ground and excited subbands.

  15. Turbulent drag in a rotating frame

    CERN Document Server

    Campagne, Antoine; Gallet, Basile; Cortet, Pierre-Philippe; Moisy, Frédéric

    2016-01-01

    What is the turbulent drag force experienced by an object moving in a rotating fluid? This open and fundamental question can be addressed by measuring the torque needed to drive an impeller at constant angular velocity $\\omega$ in a water tank mounted on a platform rotating at a rate $\\Omega$. We report a dramatic reduction in drag as $\\Omega$ increases, down to values as low as $12$\\% of the non-rotating drag. At small Rossby number $Ro = \\omega/\\Omega$, the decrease in drag coefficient $K$ follows the approximate scaling law $K \\sim Ro$, which is predicted in the framework of nonlinear inertial wave interactions and weak-turbulence theory. However, stereoscopic particle image velocimetry measurements indicate that this drag reduction rather originates from a weakening of the turbulence intensity in line with the two-dimensionalization of the large-scale flow.

  16. Drag Reduction by Microvortexes in Transverse Microgrooves

    Directory of Open Access Journals (Sweden)

    Bao Wang

    2014-07-01

    Full Text Available A transverse microgrooved surface was employed here to reduce the surface drag force by creating a slippage in bottom layer in turbulent boundary layer. A detailed simulation and experimental investigation on drag reduction by transverse microgrooves were given. The computational fluid dynamics simulation, using RNG k-ε turbulent model, showed that the vortexes were formed in the grooves and they were a main reason for the drag reduction. On the upside of the vortex, the revolving direction was consistent with the main flow, which decreased the flow shear stress by declining the velocity gradient. The experiments were carried out in a high-speed water tunnel with flow velocity varying from 17 to 19 m/s. The experimental results showed that the drag reduction was about 13%. Therefore, the computational and experimental results were cross-checked and consistent with each other to prove that the presented approach achieved effective drag reduction underwater.

  17. Idea Hubs as Nexus of Collective Creativity in Digital Innovation

    DEFF Research Database (Denmark)

    Ciriello, Raffaele; Richter, Alexander

    2015-01-01

    on instances of idea hubs in two multinational European software companies, where we conducted a case study over a two-year period, and collected data in form of interviews, digital documents, and participant observations. In doing so, we identify a set of social networking practices in which idea hubs serve......Digital innovation radically transforms the nature of corporate innovation practices, implying a growing need for deeper understanding its origins and outcomes. In this paper, we conceptualize the focal points of social networking in digital innovation as idea hubs. We focus our analysis...... as nexus of collective creativity and subject these to a critical dialectical examination. We discuss three influencing factors of idea hub choice, namely material infrastructure, innovation process phase, and personal characteristics. These explain why in a corporate environment, despite a variety...

  18. 14 CFR 398.2 - Number and designation of hubs.

    Science.gov (United States)

    2010-01-01

    ... origin and designation data; (iv) The distance of candidate hubs from the eligible place; and (v) The... may instead require that service from an eligible place be provided to a nearby focal point...

  19. Model of Controlling the Hubs in P2P Networks

    Directory of Open Access Journals (Sweden)

    Yuhua Liu

    2009-06-01

    Full Text Available Research into the hubs in Peer-to-Peer (P2P networks, and present a new method to avoid generating the hubs in the networks by controlling the logical topology structure of P2P networks. We firstly introduce the controlling ideas about hierarchizing the hubs. Then, we disclose and interpret the controlling model, and give out the concrete method to carry it out. Finally, we validate our controlling model via simulations and the simulation results demonstrate that our work is effective to control the hubs in P2P networks. Thus, this model can improve the network competence to defend against coordinated attacks, promote the network robustness, and ensure the network would develop continually and healthily.

  20. A Flexible Logistics Distribution Hub Model considering Cost Weighted Time

    Directory of Open Access Journals (Sweden)

    Wenxue Ran

    2017-01-01

    Full Text Available The delivery time of order has become an important fact for customers to evaluate logistics services. Due to the diverse and large quantities of orders in the background of electronic commerce, how to improve the flexibility of distribution hub and reduce the waiting time of customers becomes one of the most challenging questions for logistics companies. With this in mind, this paper proposes a new method of flexibility assessment in distribution hub by introducing cost weighted time (CWT. The advantages of supply hub operation mode in delivery flexibility are verified by the approach: the mode has pooling effects and uniform distribution characteristics; these traits can reduce overlapping delivery time to improve the flexibility in the case of two suppliers. Numerical examples show that the supply hub operation mode is more flexible than decentralized distribution operation mode in multidelivery cycles.

  1. Establishing a Global Halal Hub: In-Depth Interviews

    Directory of Open Access Journals (Sweden)

    Mahdi Borzooei

    2013-10-01

    Full Text Available The purpose of this study is to explore the requirements needed for a country to establish itself as a global Halal hub. In this regard, this exploratory research paper uses a semi-structured in-depth interview to obtain the perceptions of Halal experts about the requirements for establishing a Halal hub. The results of the study indicate that human capital, media, research and development, events, country’s capability, public and governmental support, marketing strategy, and infrastructure comprise the vital requirements. Furthermore, from the perceptions of the experts, public and governmental support, marketing strategy, and human capital are the three most important requirements. Since this paper is an exploratory study, it provides some insights of the three experts on the establishing of a Halal hub. In addition, a quantitative study is an appropriate approach to implement the findings of this study empirically and to determine the effective components to establish a Halal hub in those countries that desire it. A practical implication of this study is the opening of a new window for any country that aspires to be a Halal hub. In this matter, this paper presents the key considerations in establishing a Halal hub for Halal certification bodies, companies and marketers involved in the Halal business. Moreover, this research attempts to influence the perceptions and attitudes of people of the country on the desirability of becoming a Halal hub, followed by a discussion on the development of a national brand. When the contribution of its people is high, a country stands the best chance of achieving its goal. Finally, this study is one of the first to seek the perceptions of experts about vital requirements that a country should pay more attention to if it wishes to establish a global Halal hub.

  2. A Hub Matrix Theory and Applications to Wireless Communications

    Directory of Open Access Journals (Sweden)

    Kung HT

    2007-01-01

    Full Text Available This paper considers communications and network systems whose properties are characterized by the gaps of the leading eigenvalues of for a matrix . It is shown that a sufficient and necessary condition for a large eigen-gap is that is a "hub" matrix in the sense that it has dominant columns. Some applications of this hub theory in multiple-input and multiple-output (MIMO wireless systems are presented.

  3. Why do European companies have Innovation Hubs in Silicon Valley

    DEFF Research Database (Denmark)

    Berger, Andreas; Brem, Alexander

    2017-01-01

    Innovation hubs are gaining high attention in recent years, especially from European companies. Silicon Valley has been deemed as one of the most attractive and successful environments for establishing innovation hubs. This article highlights examples of companies from Europe that made the step t...... to California—namely, Volkswagen, Swisscom, BMW, Axel Springer, Munich Re, and Innogy SE (RWE Group). Based on these companies’ experiences, recommendations are given on how companies might approach a setup in Silicon Valley for long-term success....

  4. Fairness Through Awareness

    CERN Document Server

    Dwork, Cynthia; Pitassi, Toniann; Reingold, Omer; Zemel, Rich

    2011-01-01

    "What can be learned about from the sole fact that I have been shown this on-line advertisement?" By definition, the answer to this question is non-trivial whenever advertisements are not served indiscriminately. Advertisers, hoping to have targeted precisely and appropriately, use information from multiple sources to give different on-line experiences to different people. Thus the message of "giving you the ads that interest you" does not tell the whole story of behavioral targeting, and the resulting differentiation in user experience may, or may not, work to the advantage of the user. When it results in differential pricing it arguably does not benefit some users; when it results in steering minorities away from certain neighborhoods or toward less advantageous credit card offerings, it is illegal. This raises the question of fairness in advertising, and, more generally, of fairness in classification. This rather broad topic is not restricted to the digital world, and encompasses classification in such div...

  5. On a fair verdict

    Directory of Open Access Journals (Sweden)

    Sergei G. Ol'kov

    2014-01-01

    Full Text Available Objective the study of the phenomenon of justice in general and fairness in judicial verdicts in particular. Methods 1 observation 2 deduction 3 use of the laws of formal logic 4 comparative analysis 5 formal legal 6 mathematical modeling. Results the author considers the possibility of creating the scale of good and evil. As a result of rendering of legal laws in the language of mathematics were obtained the following conclusions 1 definition of justice as equality between the objective truth of the real world X and the subjective evaluation of this truth Y Y X assessment is on the line of justice in the Cartesian coordinate system if the deeds axis is correctly scaled ndash quotso it actually is and this is our answerrdquo the fair sentence is an accurate evaluation by the court the value of punishment of the deed the legal relations subject with the exact scaling of deeds and punishments axes y x where y is the assessment x ndash deed 2 general suggestions for scaling coordinate axes of deeds abscissa and penalties ordinates ndash proposal on the need to develop scales of relations for valuation of objects ndash deeds and evaluation as it is ndash the scale of punishments 3 grounds for the idea that not every degree or measure of the consistency of the realworld objects estimation by a wide range of evaluation subjects is fair justice 4 identification of the range of existing problems in the judicial practice in making fair sentences anbspthe absence in the criminal law of the clear scales of deeds and punishments the legislator does not give a clear estimation of the deed but establishes either continuous or multiple evaluation b modern legislator cannot give absolute scale of good and evil but specifies a relative scale in implicit form dependent on time place method of organization of power in the state ideas of the society about good and evil and justice. As a result the relative scale is quotslidingquot in time and space c the

  6. Bargaining and fairness.

    Science.gov (United States)

    Binmore, Kenneth

    2014-07-22

    The idea that human morality might be the product of evolution is not popular. The reason is partly that the moral principles that actually govern our day-to-day behavior have been idealized in a way that makes a natural origin seem impossible. This paper puts the case for a more down-to-earth assessment of human morality by arguing that the evolution of our sense of fairness can be traced to the practicalities of food-sharing. When animals share food, they can be seen as enjoying the fruits of an implicit bargain to ensure each other against hunger. The implications of this observation are explored using the tools of game theory. The arguments lead to a structure for fair bargains that closely resembles the structure proposed by John Rawls, the leading moral philosopher of the last century.

  7. Concerted perturbation observed in a hub network in Alzheimer's disease.

    Directory of Open Access Journals (Sweden)

    Dapeng Liang

    Full Text Available Alzheimer's disease (AD is a progressive neurodegenerative disease involving the alteration of gene expression at the whole genome level. Genome-wide transcriptional profiling of AD has been conducted by many groups on several relevant brain regions. However, identifying the most critical dys-regulated genes has been challenging. In this work, we addressed this issue by deriving critical genes from perturbed subnetworks. Using a recent microarray dataset on six brain regions, we applied a heaviest induced subgraph algorithm with a modular scoring function to reveal the significantly perturbed subnetwork in each brain region. These perturbed subnetworks were found to be significantly overlapped with each other. Furthermore, the hub genes from these perturbed subnetworks formed a connected hub network consisting of 136 genes. Comparison between AD and several related diseases demonstrated that the hub network was robustly and specifically perturbed in AD. In addition, strong correlation between the expression level of these hub genes and indicators of AD severity suggested that this hub network can partially reflect AD progression. More importantly, this hub network reflected the adaptation of neurons to the AD-specific microenvironment through a variety of adjustments, including reduction of neuronal and synaptic activities and alteration of survival signaling. Therefore, it is potentially useful for the development of biomarkers and network medicine for AD.

  8. On a fair verdict

    OpenAIRE

    Sergei G. Ol'kov

    2014-01-01

    Objective the study of the phenomenon of justice in general and fairness in judicial verdicts in particular. Methods 1 observation 2 deduction 3 use of the laws of formal logic 4 comparative analysis 5 formal legal 6 mathematical modeling. Results the author considers the possibility of creating the scale of good and evil. As a result of rendering of legal laws in the language of mathematics were obtained the following conclusions 1 definition of justice as equality between the object...

  9. Science Fair Art

    Science.gov (United States)

    Sullivan, Kevin

    2004-01-01

    Sciences fair season is a time when seasoned non-science teachers typically give up all hope of cramming any more knowledge into the heads of their students. It's just too much. However, non-science types might be missing out on a pretty good deal. The science department has got these kids in a pretty tight grip as far as the process and the…

  10. Justice, fairness, and enhancement.

    Science.gov (United States)

    Savulescu, Julian

    2006-12-01

    This article begins by considering four traditional definitions of enhancement, then proposes a fifth, the Welfarist definition. It then considers fairness-based objections to enhancement, using the example of performance enhancement in sport. In so doing it defines sport and the values proper to it, surveys alternative theories of justice, considers the natural distribution of capabilities and disabilities, and draws a distinction between social, psychological, and biological enhancement. The article advances a new argument that justice requires enhancement.

  11. Giant Frictional Drag in Double Bilayer Graphene Heterostructures

    Science.gov (United States)

    Lee, Kayoung; Xue, Jiamin; Dillen, David C.; Watanabe, Kenji; Taniguchi, Takashi; Tutuc, Emanuel

    2016-07-01

    We study the frictional drag between carriers in two bilayer graphene flakes separated by a 2-5 nm thick hexagonal boron nitride dielectric. At temperatures (T ) lower than ˜10 K , we observe a large anomalous negative drag emerging predominantly near the drag layer charge neutrality. The anomalous drag resistivity increases dramatically with reducing T , and becomes comparable to the layer resistivity at the lowest T =1.5 K . At low T the drag resistivity exhibits a breakdown of layer reciprocity. A comparison of the drag resistivity and the drag layer Peltier coefficient suggests a thermoelectric origin of this anomalous drag.

  12. FAIR-share

    CERN Multimedia

    2009-01-01

    Twenty-seven engineers involved in the FAIR project in Germany recently spent three days at CERN. The purpose of their visit: tour ALICE and meet with CERN engineers. This marks the start of a close cooperation. The FAIR project engineers and their CERN counterparts.If you want to build a new particle accelerator and wish to benefit from existing expertise, who do you go to see? Well… why not go straight to CERN? That’s what this group of 27 engineers did. They are working on a new accelerator project, the Facility for Antiproton and Ion Research (FAIR), to be built at the heavy-ion research centre GSI located near Darmstadt, Germany. Representing a variety of disciplines, from manufacturing to architecture, they will be responsible for making the project a reality. The visit was organised from 14-16 October, making it possible to include a tour of the ALICE experiment prior to the re-start of the LHC. However, the main goal was ...

  13. On the Minimum Induced Drag of Wings

    Science.gov (United States)

    Bowers, Albion H.

    2011-01-01

    Of all the types of drag, induced drag is associated with the creation and generation of lift over wings. Induced drag is directly driven by the span load that the aircraft is flying at. The tools by which to calculate and predict induced drag we use were created by Ludwig Prandtl in 1903. Within a decade after Prandtl created a tool for calculating induced drag, Prandtl and his students had optimized the problem to solve the minimum induced drag for a wing of a given span, formalized and written about in 1920. This solution is quoted in textbooks extensively today. Prandtl did not stop with this first solution, and came to a dramatically different solution in 1932. Subsequent development of this 1932 solution solves several aeronautics design difficulties simultaneously, including maximum performance, minimum structure, minimum drag loss due to control input, and solution to adverse yaw without a vertical tail. This presentation lists that solution by Prandtl, and the refinements by Horten, Jones, Kline, Viswanathan, and Whitcomb.

  14. The role of drag in insect hovering.

    Science.gov (United States)

    Wang, Z Jane

    2004-11-01

    Studies of insect flight have focused on aerodynamic lift, both in quasi-steady and unsteady regimes. This is partly influenced by the choice of hovering motions along a horizontal stroke plane, where aerodynamic drag makes no contribution to the vertical force. In contrast, some of the best hoverers--dragonflies and hoverflies--employ inclined stroke planes, where the drag in the down- and upstrokes does not cancel each other. Here, computation of an idealized dragonfly wing motion shows that a dragonfly uses drag to support about three quarters of its weight. This can explain an anomalous factor of four in previous estimates of dragonfly lift coefficients, where drag was assumed to be small. To investigate force generation and energy cost of hovering flight using different combination of lift and drag, I study a family of wing motion parameterized by the inclined angle of the stroke plane. The lift-to-drag ratio is no longer a measure of efficiency, except in the case of horizontal stroke plane. In addition, because the flow is highly stalled, lift and drag are of comparable magnitude, and the aerodynamic efficiency is roughly the same up to an inclined angle about 60 degrees , which curiously agrees with the angle observed in dragonfly flight. Finally, the lessons from this special family of wing motion suggests a strategy for improving efficiency of normal hovering, and a unifying view of different wing motions employed by insects.

  15. Coulomb drag between helical Luttinger liquids

    Science.gov (United States)

    Kainaris, N.; Gornyi, I. V.; Levchenko, A.; Polyakov, D. G.

    2017-01-01

    We theoretically study Coulomb drag between two helical edges with broken spin-rotational symmetry, such as would occur in two capacitively coupled quantum spin Hall insulators. For the helical edges, Coulomb drag is particularly interesting because it specifically probes the inelastic interactions that break the conductance quantization for a single edge. Using the kinetic equation formalism, supplemented by bosonization, we find that the drag resistivity ρD exhibits a nonmonotonic dependence on the temperature T . In the limit of low T ,ρD vanishes with decreasing T as a power law if intraedge interactions are not too strong. This is in stark contrast to Coulomb drag in conventional quantum wires, where ρD diverges at T →0 irrespective of the strength of repulsive interactions. Another unusual property of Coulomb drag between the helical edges concerns higher T for which, unlike in the Luttinger liquid model, drag is mediated by plasmons. The special type of plasmon-mediated drag can be viewed as a distinguishing feature of the helical liquid—because it requires peculiar umklapp scattering only available in the presence of a Dirac point in the electron spectrum.

  16. Orographic drag uncertainties impact forecast skill

    Science.gov (United States)

    Sandu, Irina; Zadra, Ayrton; Wedi, Nils; Bacmeister, Julio

    2017-04-01

    Despite their importance for the large-scale circulation, to date the representation of drag processes remains a major source of uncertainty in global models. Among the different drag processes the representation of orographic drag is particularly challenging. This has been recently highlighted by the WMO Working Group on Numerical Experimentation (WGNE) 'Drag project' which demonstrated that the main NWP and climate models differ significantly in representation of the total parameterized surface stress and in the partitioning of surface stress among various physical processes, particularly in regions with orography. Here we discuss how uncertain is the representation of orographic drag in models, and we illustrate how this uncertainty affects the skill of medium range weather forecasts. Namely we show how different is the representation of the resolved orography even in models with similar headline horizontal resolution. We also use the results of the WGNE 'Drag project' to illustrate how much models differ in terms of the total parameterized surface stress and its partition among various processes. Finally, we use the Integrated Forecasting System of ECMWF to demonstrate how much these intermodel differences either in the resolved orography or the representation subgrid drag affect the forecast skill.

  17. Process Fairness and Dynamic Consistency

    NARCIS (Netherlands)

    S.T. Trautmann (Stefan); P.P. Wakker (Peter)

    2010-01-01

    textabstractAbstract: When process fairness deviates from outcome fairness, dynamic inconsistencies can arise as in nonexpected utility. Resolute choice (Machina) can restore dynamic consistency under nonexpected utility without using Strotz's precommitment. It can similarly justify dynamically

  18. Drag and Torque on Locked Screw Propeller

    Directory of Open Access Journals (Sweden)

    Tomasz Tabaczek

    2014-09-01

    Full Text Available Few data on drag and torque on locked propeller towed in water are available in literature. Those data refer to propellers of specific geometry (number of blades, blade area, pitch and skew of blades. The estimation of drag and torque of an arbitrary propeller considered in analysis of ship resistance or propulsion is laborious. The authors collected and reviewed test data available in the literature. Based on collected data there were developed the empirical formulae for estimation of hydrodynamic drag and torque acting on locked screw propeller. Supplementary CFD computations were carried out in order to prove the applicability of the formulae to modern moderately skewed screw propellers.

  19. Drag Reduction by Leidenfrost Vapor Layers

    Science.gov (United States)

    Vakarelski, Ivan U.; Marston, Jeremy O.; Chan, Derek Y. C.; Thoroddsen, Sigurdur T.

    2011-05-01

    We demonstrate and quantify a highly effective drag reduction technique that exploits the Leidenfrost effect to create a continuous and robust lubricating vapor layer on the surface of a heated solid sphere moving in a liquid. Using high-speed video, we show that such vapor layers can reduce the hydrodynamic drag by over 85%. These results appear to approach the ultimate limit of drag reduction possible by different methods based on gas-layer lubrication and can stimulate the development of related energy saving technologies.

  20. Frame-Dragging from Charged Rotating Body

    CERN Document Server

    Dubey, Anuj Kumar

    2016-01-01

    In the present paper, we have considered the three parameters: mass, charge and rotation to discuss their combined effect on frame dragging for a charged rotating body. If we consider the ray of light which is emitted radially outward from a rotating body then the frame dragging shows a periodic nature with respect to coordinate $\\phi$ (azimuthal angle). It has been found that the value of frame dragging obtains a maximum at, $ \\phi =\\frac{\\pi}{2}$ and a minimum at $ \\phi =\\frac{3 \\pi}{2}$.

  1. Drag Reduction by Leidenfrost Vapor Layers

    KAUST Repository

    Vakarelski, Ivan Uriev

    2011-05-23

    We demonstrate and quantify a highly effective drag reduction technique that exploits the Leidenfrost effect to create a continuous and robust lubricating vapor layer on the surface of a heated solid sphere moving in a liquid. Using high-speed video, we show that such vapor layers can reduce the hydrodynamic drag by over 85%. These results appear to approach the ultimate limit of drag reduction possible by different methods based on gas-layer lubrication and can stimulate the development of related energy saving technologies.

  2. NCLEX fairness and sensitivity review.

    Science.gov (United States)

    Wendt, Anne; Kenny, Lorraine; Riley, Michelle

    2009-01-01

    The National Council Licensing Examination is an examination that is used for the purpose of licensing registered nurses and practical/vocational nurses. To help ensure that the examination questions (items) are fair and unbiased, all items undergo a fairness and sensitivity review as part of the item development process. This article focuses on the fairness and sensitivity review.

  3. Fairness in Multicultural Assessment Systems

    Science.gov (United States)

    Stobart, Gordon

    2005-01-01

    This paper is about fairness (equity) in large-scale assessment systems within multicultural societies. It makes the key assumptions that fairness is fundamentally a sociocultural, rather than a technical, issue and that fair assessment cannot be considered in isolation from both the curriculum and the educational opportunities of the students.…

  4. Fractions: How to Fair Share

    Science.gov (United States)

    Wilson, P. Holt; Edgington, Cynthia P.; Nguyen, Kenny H.; Pescosolido, Ryan S.; Confrey, Jere

    2011-01-01

    Children learn from a very early age what it means to get their "fair share." Whether it is candy or birthday cake, many children successfully create equal-size groups or parts of a collection or whole but later struggle to create fair shares of multiple wholes, such as fairly sharing four pies among a family of seven. Recent research suggests…

  5. Drag bias feedback for the analytic drag control entry guidance system. [for the space shuttle orbiter

    Science.gov (United States)

    Kyle, H. C.

    1976-01-01

    The Analytic Drag Control (ADC) entry guidance has been developed and baselined for the space shuttle orbiter entry. A method is presented which corrects the orbiter entry guidance commanded bank angle for biases between navigated drag and guidance computed reference drag. This is accomplished by an integral feedback technique, which uses the drag bias information to adjust the difference between navigated and reference altitude rate used by the ADC guidance. The method improves the capability of the ADC guidance system by compensating for any error source which causes a bias between the navigated drag and reference drag profile. These errors include navigated altitude rate errors, atmosphere dispersions, and roll attitude deadband effects. A discussion of the method and results of digital computer entry simulations is presented.

  6. The Effects of Hub Drag, Solidity, Dual Rotation, and Number of Blades upon the Efficiency of High-Pitch Propellers

    Science.gov (United States)

    1941-10-01

    UBC of v m y h i 3 p i t c h propol lc rs Ts net ncccs?a.ril.jr accofipmiod by a s ~ r i o i ~ s 1-0~s of ncy; i n f a c t , it i s ap...t h a t of the fmr -b lade I n prcvious compsrisons of s ing le- and d u a l - r o t a t i n g propol lc rs , a t t e n t i o n has been

  7. Identification of promising Twin Hub networks: Report of Work Package 1 of the Intermodal rail freight Twin hub Network Northwest Europe - project (final report)

    NARCIS (Netherlands)

    Kreutzberger, E.D.; Konings, J.W.; Meijer, S.; Witteveen, C.; Meijers, B.M.; Pekin, E.; Macharis, C.; Kiel, J.; Kawabata, Y.; Vos, W.

    2014-01-01

    This report is the first deliverable of the project Intermodal Rail Freight Twin Hub Network Northwest Europe. We call its subject Twin hub network and the organisational entity to carry out the actions the Twin hub project. The project is funded by INTERREG NWE (programme IVb). Its work started in

  8. Bubble Drag Reduction Requires Large Bubbles

    Science.gov (United States)

    Verschoof, Ruben A.; van der Veen, Roeland C. A.; Sun, Chao; Lohse, Detlef

    2016-09-01

    In the maritime industry, the injection of air bubbles into the turbulent boundary layer under the ship hull is seen as one of the most promising techniques to reduce the overall fuel consumption. However, the exact mechanism behind bubble drag reduction is unknown. Here we show that bubble drag reduction in turbulent flow dramatically depends on the bubble size. By adding minute concentrations (6 ppm) of the surfactant Triton X-100 into otherwise completely unchanged strongly turbulent Taylor-Couette flow containing bubbles, we dramatically reduce the drag reduction from more than 40% to about 4%, corresponding to the trivial effect of the bubbles on the density and viscosity of the liquid. The reason for this striking behavior is that the addition of surfactants prevents bubble coalescence, leading to much smaller bubbles. Our result demonstrates that bubble deformability is crucial for bubble drag reduction in turbulent flow and opens the door for an optimization of the process.

  9. Bubble drag reduction requires large bubbles

    CERN Document Server

    Verschoof, Ruben A; Sun, Chao; Lohse, Detlef

    2016-01-01

    In the maritime industry, the injection of air bubbles into the turbulent boundary layer under the ship hull is seen as one of the most promising techniques to reduce the overall fuel consumption. However, the exact mechanism behind bubble drag reduction is unknown. Here we show that bubble drag reduction in turbulent flow dramatically depends on the bubble size. By adding minute concentrations (6 ppm) of the surfactant Triton X-100 into otherwise completely unchanged strongly turbulent Taylor-Couette flow containing bubbles, we dramatically reduce the drag reduction from more than 40% to about 4%, corresponding to the trivial effect of the bubbles on the density and viscosity of the liquid. The reason for this striking behavior is that the addition of surfactants prevents bubble coalescence, leading to much smaller bubbles. Our result demonstrates that bubble deformability is crucial for bubble drag reduction in turbulent flow and opens the door for an optimization of the process.

  10. The physics of orographic gravity wave drag

    Directory of Open Access Journals (Sweden)

    Miguel A C Teixeira

    2014-07-01

    Full Text Available The drag and momentum fluxes produced by gravity waves generated in flow over orography are reviewed, focusing on adiabatic conditions without phase transitions or radiation effects, and steady mean incoming flow. The orographic gravity wave drag is first introduced in its simplest possible form, for inviscid, linearized, non-rotating flow with the Boussinesq and hydrostatic approximations, and constant wind and static stability. Subsequently, the contributions made by previous authors (primarily using theory and numerical simulations to elucidate how the drag is affected by additional physical processes are surveyed. These include the effect of orography anisotropy, vertical wind shear, total and partial critical levels, vertical wave reflection and resonance, non-hydrostatic effects and trapped lee waves, rotation and nonlinearity. Frictional and boundary layer effects are also briefly mentioned. A better understanding of all of these aspects is important for guiding the improvement of drag parametrization schemes.

  11. Drag sails for space debris mitigation

    Science.gov (United States)

    Visagie, Lourens; Lappas, Vaios; Erb, Sven

    2015-04-01

    The prudence for satellites to have a mitigation or deorbiting strategy has been brought about by the ever increasing amount of debris in Earth orbit. Drag augmentation is a potentially passive method for de-orbiting in LEO but its collision risk mitigation efficiency is sometimes underestimated by not taking all the relevant factors into account. This paper shows that using drag augmentation from a deployable drag-sail to de-orbit a satellite in LEO will lead to a reduction in collision risk. In order to support this finding, the models that are needed in order to evaluate the collision risk of a decaying object under drag conditions are presented. A comparison is performed between the simpler Area-Time-Product (ATP) and more precise collision risk analysis, and the effects that are overlooked in the simple ATP calculation are explained.

  12. Integrated lift/drag controller for aircraft

    Science.gov (United States)

    Olcott, J. W.; Seckel, E.; Ellis, D. R. (Inventor)

    1974-01-01

    A system for altering the lift/drag characteristics of powered aircraft to provide a safe means of glide path control includes a control device integrated for coordination action with the aircraft throttle. Such lift/drag alteration devices as spoilers, dive brakes, and the like are actuated by manual operation of a single lever coupled with the throttle for integrating, blending or coordinating power control. Improper operation of the controller is inhibited by safety mechanisms.

  13. Flow drag and heat transfer characteristics of drag-reducing nanofluids with CuO nanoparticles

    Science.gov (United States)

    Wang, Ping-Yang; Wang, Xue-Jiao; Liu, Zhen-Hua

    2017-02-01

    A new kind of aqueous CuO nanofluid with drag-reducing performance was developed. The new working fluid was an aqueous CTAC (cetyltrimethyl ammonium chloride) solution with CuO nanoparticles added and has both special effects of drag-reducing and heat transfer enhancement. An experiment was carried out to investigate the forced convective flow and heat transfer characteristics of conventional drag reducing fluid (aqueous CTAC solution) and the new drag-reducing nanofluid in a test tube with an inner diameter of 25.6 mm. Results indicated that there were no obvious differences of the drag-reducing characteristics between conventional drag reducing fluid and new drag-reducing nanofluid. However, their heat transfer characteristics were obvious different. The heat transfer characteristics of the new drag-reducing nanofluid significantly depend on the liquid temperature, the nanoparticle concentration and the CTAC concentration. The heat transfer enhancement technology of nanofluid could be applied to solve the problem of heat transfer deterioration for conventional drag-reducing fluids.

  14. Flow drag and heat transfer characteristics of drag-reducing nanofluids with CuO nanoparticles

    Science.gov (United States)

    Wang, Ping-Yang; Wang, Xue-Jiao; Liu, Zhen-Hua

    2016-05-01

    A new kind of aqueous CuO nanofluid with drag-reducing performance was developed. The new working fluid was an aqueous CTAC (cetyltrimethyl ammonium chloride) solution with CuO nanoparticles added and has both special effects of drag-reducing and heat transfer enhancement. An experiment was carried out to investigate the forced convective flow and heat transfer characteristics of conventional drag reducing fluid (aqueous CTAC solution) and the new drag-reducing nanofluid in a test tube with an inner diameter of 25.6 mm. Results indicated that there were no obvious differences of the drag-reducing characteristics between conventional drag reducing fluid and new drag-reducing nanofluid. However, their heat transfer characteristics were obvious different. The heat transfer characteristics of the new drag-reducing nanofluid significantly depend on the liquid temperature, the nanoparticle concentration and the CTAC concentration. The heat transfer enhancement technology of nanofluid could be applied to solve the problem of heat transfer deterioration for conventional drag-reducing fluids.

  15. Bioinspired surfaces for turbulent drag reduction.

    Science.gov (United States)

    Golovin, Kevin B; Gose, James W; Perlin, Marc; Ceccio, Steven L; Tuteja, Anish

    2016-08-06

    In this review, we discuss how superhydrophobic surfaces (SHSs) can provide friction drag reduction in turbulent flow. Whereas biomimetic SHSs are known to reduce drag in laminar flow, turbulence adds many new challenges. We first provide an overview on designing SHSs, and how these surfaces can cause slip in the laminar regime. We then discuss recent studies evaluating drag on SHSs in turbulent flow, both computationally and experimentally. The effects of streamwise and spanwise slip for canonical, structured surfaces are well characterized by direct numerical simulations, and several experimental studies have validated these results. However, the complex and hierarchical textures of scalable SHSs that can be applied over large areas generate additional complications. Many studies on such surfaces have measured no drag reduction, or even a drag increase in turbulent flow. We discuss how surface wettability, roughness effects and some newly found scaling laws can help explain these varied results. Overall, we discuss how, to effectively reduce drag in turbulent flow, an SHS should have: preferentially streamwise-aligned features to enhance favourable slip, a capillary resistance of the order of megapascals, and a roughness no larger than 0.5, when non-dimensionalized by the viscous length scale.This article is part of the themed issue 'Bioinspired hierarchically structured surfaces for green science'.

  16. Why Do Hubs Tend to Be Essential in Protein Networks?

    Directory of Open Access Journals (Sweden)

    2006-06-01

    Full Text Available The protein-protein interaction (PPI network has a small number of highly connected protein nodes (known as hubs and many poorly connected nodes. Genome-wide studies show that deletion of a hub protein is more likely to be lethal than deletion of a non-hub protein, a phenomenon known as the centrality-lethality rule. This rule is widely believed to reflect the special importance of hubs in organizing the network, which in turn suggests the biological significance of network architectures, a key notion of systems biology. Despite the popularity of this explanation, the underlying cause of the centrality-lethality rule has never been critically examined. We here propose the concept of essential PPIs, which are PPIs that are indispensable for the survival or reproduction of an organism. Our network analysis suggests that the centrality-lethality rule is unrelated to the network architecture, but is explained by the simple fact that hubs have large numbers of PPIs, therefore high probabilities of engaging in essential PPIs. We estimate that ~ 3% of PPIs are essential in the yeast, accounting for ~ 43% of essential genes. As expected, essential PPIs are evolutionarily more conserved than nonessential PPIs. Considering the role of essential PPIs in determining gene essentiality, we find the yeast PPI network functionally more robust than random networks, yet far less robust than the potential optimum. These and other findings provide new perspectives on the biological relevance of network structure and robustness.

  17. Why do hubs tend to be essential in protein networks?

    Directory of Open Access Journals (Sweden)

    Xionglei He

    2006-06-01

    Full Text Available The protein-protein interaction (PPI network has a small number of highly connected protein nodes (known as hubs and many poorly connected nodes. Genome-wide studies show that deletion of a hub protein is more likely to be lethal than deletion of a non-hub protein, a phenomenon known as the centrality-lethality rule. This rule is widely believed to reflect the special importance of hubs in organizing the network, which in turn suggests the biological significance of network architectures, a key notion of systems biology. Despite the popularity of this explanation, the underlying cause of the centrality-lethality rule has never been critically examined. We here propose the concept of essential PPIs, which are PPIs that are indispensable for the survival or reproduction of an organism. Our network analysis suggests that the centrality-lethality rule is unrelated to the network architecture, but is explained by the simple fact that hubs have large numbers of PPIs, therefore high probabilities of engaging in essential PPIs. We estimate that approximately 3% of PPIs are essential in the yeast, accounting for approximately 43% of essential genes. As expected, essential PPIs are evolutionarily more conserved than nonessential PPIs. Considering the role of essential PPIs in determining gene essentiality, we find the yeast PPI network functionally more robust than random networks, yet far less robust than the potential optimum. These and other findings provide new perspectives on the biological relevance of network structure and robustness.

  18. Fairness in scientific publishing

    Science.gov (United States)

    Matthews, Philippa C.

    2017-01-01

    Major changes are afoot in the world of academic publishing, exemplified by innovations in publishing platforms, new approaches to metrics, improvements in our approach to peer review, and a focus on developing and encouraging open access to scientific literature and data. The FAIR acronym recommends that authors and publishers should aim to make their output Findable, Accessible, Interoperable and Reusable. In this opinion article, I explore the parallel view that we should take a collective stance on making the dissemination of scientific data fair in the conventional sense, by being mindful of equity and justice for patients, clinicians, academics, publishers, funders and academic institutions. The views I represent are founded on oral and written dialogue with clinicians, academics and the publishing industry. Further progress is needed to improve collaboration and dialogue between these groups, to reduce misinterpretation of metrics, to minimise inequity that arises as a consequence of geographic setting, to improve economic sustainability, and to broaden the spectrum, scope, and diversity of scientific publication.

  19. CERN Book fair

    CERN Multimedia

    CERN Central Library and IT Department Bookshop

    2004-01-01

    The CERN Library, in conjunction with the IT Department Bookshop, is organizing a book fair on the 28th and 29th October. Some 15 major publishers will be represented, including 6 who will be here in person, and more than 700 of their latest titles will be on display (for sale or order). The major topics covered will be computing, physics, technology, mathematics, engineering and popular science. Those present at this event will include Alpha Science, Cambridge University Press, Elsevier, Institute of Physics, Microsoft Press, O'Reilly, OLF Switzerland, Oxford University Press, McGraw-Hill, Springer, Pearson, Thali Switzerland, Wiley, World Scientific and Ebooks Corporation. The fair will take place on the first floor of the Main Building (bldg.60), Salle des Pas Perdus, and will be open from 10.00 to 17.00 on both days. In addition, EBooks Corporation will describe their electronic book system; insight into this is available at http://www.eblib.com/ We look forward to your support for this initiative. Sh...

  20. A method for measuring skin friction drag on a flat plate in contaminated gas flows

    Science.gov (United States)

    Oetting, R. B.; Patterson, G. K.

    1984-01-01

    A technique for measuring friction drag in turbulent gas and gas/particle flows over flat plates is presented, and preliminary results are reported. A 0.25-in.-thick 72 x 6-in. Al plate is suspended by six horizontal support air bearings and four vertical alignment air bearings between fixed dummy plates and leading-edge and trailing-edge fairings in the 32-in.-high 48-in.-wide 11-ft-long test section of a closed-circuit atmospheric wind tunnel operating at 50-150 ft/sec. Particles of Fe and Al oxides of diameter 20-150 microns and density up to 0.3 lb particles per lb air are injected via a 6 x 0.167-in. nozzle; turbulence is induced by a roughened section of the leading-edge fairing; and friction drag is measured using a load-cell pressure transducer. Sample results are shown in a graph, demonstrating good agreement with theoretical drag calculations.

  1. On the Fair Play Spirit%论Fair Play

    Institute of Scientific and Technical Information of China (English)

    张维; 林琳

    2011-01-01

    采用文献资料法,历史分析了"Fair Play"精神的起源,并结合Fair Play精神面临的时代压力,探讨现代体育生命力延续的议题,提出"人"才是体育及其"Fair Play"精神继续生存或走向毁灭的主宰者.

  2. New approaches to the marine transport hub competitive growth

    Directory of Open Access Journals (Sweden)

    M. V. Botnaryuk

    2010-12-01

    Full Text Available The issues of marine transport hub competitive growth in the context of new economic conditions are considered in the paper. Analyzing the present tools of the transport hub competitive growth, the author emphasizes their production-logistics orientation. However, when rendering services to cargo and ship owners, members of the MTH establish official (contractual and informal relationship and exchange information on a permanent basis. The research into the nature of such a relationship brought the author to the conclusion that generation and further development of the partnership is a basis for new ways of the transport hub competitive growth. Considering the MTH as an institution, the author suggests that a general marketing information system intended for improvement of the services rendered, which will undeniably enhance competitive advantage.

  3. An environmental transfer hub for multimodal atom probe tomography.

    Science.gov (United States)

    Perea, Daniel E; Gerstl, Stephan S A; Chin, Jackson; Hirschi, Blake; Evans, James E

    2017-01-01

    Environmental control during transfer between instruments is required for samples sensitive to air or thermal exposure to prevent morphological or chemical changes prior to analysis. Atom probe tomography is a rapidly expanding technique for three-dimensional structural and chemical analysis, but commercial instruments remain limited to loading specimens under ambient conditions. In this study, we describe a multifunctional environmental transfer hub allowing controlled cryogenic or room-temperature transfer of specimens under atmospheric or vacuum pressure conditions between an atom probe and other instruments or reaction chambers. The utility of the environmental transfer hub is demonstrated through the acquisition of previously unavailable mass spectral analysis of an intact organic molecule made possible via controlled cryogenic transfer into the atom probe using the hub. The ability to prepare and transfer specimens in precise environments promises a means to access new science across many disciplines from untainted samples and allow downstream time-resolved in situ atom probe studies.

  4. Microfluidic hubs, systems, and methods for interface fluidic modules

    Energy Technology Data Exchange (ETDEWEB)

    Bartsch, Michael S; Claudnic, Mark R; Kim, Hanyoup; Patel, Kamlesh D; Renzi, Ronald F; Van De Vreugde, James L

    2015-01-27

    Embodiments of microfluidic hubs and systems are described that may be used to connect fluidic modules. A space between surfaces may be set by fixtures described herein. In some examples a fixture may set substrate-to-substrate spacing based on a distance between registration surfaces on which the respective substrates rest. Fluidic interfaces are described, including examples where fluid conduits (e.g. capillaries) extend into the fixture to the space between surfaces. Droplets of fluid may be introduced to and/or removed from microfluidic hubs described herein, and fluid actuators may be used to move droplets within the space between surfaces. Continuous flow modules may be integrated with the hubs in some examples.

  5. Mapping multiplex hubs in human functional brain networks

    Directory of Open Access Journals (Sweden)

    Alex Arenas

    2016-07-01

    Full Text Available Typical brain networks consist of many peripheral regions and a few highly centralones, i.e. hubs, playing key functional roles in cerebral inter-regional interactions. Studieshave shown that networks, obtained from the analysis of specific frequency components ofbrain activity, present peculiar architectures with unique profiles of region centrality. However,the identification of hubs in networks built from different frequency bands simultaneouslyis still a challenging problem, remaining largely unexplored. Here we identify eachfrequency component with one layer of a multiplex network and face this challenge by exploitingthe recent advances in the analysis of multiplex topologies. First, we show that eachfrequency band carries unique topological information, fundamental to accurately modelbrain functional networks. We then demonstrate that hubs in the multiplex network, in generaldifferent from those ones obtained after discarding or aggregating the measured signalsas usual, provide a more accurate map of brain’s most important functional regions, allowingto distinguish between healthy and schizophrenic populations better than conventionalnetwork approaches.

  6. A new method for improved hub height mean wind speed estimates using short-term hub height data

    Energy Technology Data Exchange (ETDEWEB)

    Lackner, Matthew A.; Rogers, Anthony L.; Manwell, James F.; McGowan, Jon G. [Wind Energy Center, Department of Mechanical and Industrial Engineering, University of Massachusetts Amherst, 160 Governors Dr., Amherst, MA 01003 (United States)

    2010-10-15

    The estimation of the wind resource at the hub height of a wind turbine is one of the primary goals of site assessment. Because the measurement heights of meteorological towers (met towers) are typically significantly lower than turbine hub heights, a shear model is generally needed to extrapolate the measured wind resource at the lower measurement height to the hub height of the turbine. This paper presents methods for improving the estimate of the hub height wind resource from met tower data through the use of ground-based remote sensing devices. The methods leverage the two major advantages of these devices: their portability and their ability to measure at the wind turbine hub height. Specifically, the methods rely on augmenting the one year of met tower measurements with short-term measurements from a ground-based remote sensing device. The results indicate that the methods presented are capable of producing substantial improvements in the accuracy and uncertainty of shear extrapolation predictions. The results suggest that the typical site assessment process can be reevaluated, and alternative strategies that utilize ground-based remote sensing devices can be incorporated to significantly improve the process. (author)

  7. Cotunneling Drag Effect in Coulomb-Coupled Quantum Dots

    Science.gov (United States)

    Keller, A. J.; Lim, J. S.; Sánchez, David; López, Rosa; Amasha, S.; Katine, J. A.; Shtrikman, Hadas; Goldhaber-Gordon, D.

    2016-08-01

    In Coulomb drag, a current flowing in one conductor can induce a voltage across an adjacent conductor via the Coulomb interaction. The mechanisms yielding drag effects are not always understood, even though drag effects are sufficiently general to be seen in many low-dimensional systems. In this Letter, we observe Coulomb drag in a Coulomb-coupled double quantum dot and, through both experimental and theoretical arguments, identify cotunneling as essential to obtaining a correct qualitative understanding of the drag behavior.

  8. Direct photons at FAIR

    Energy Technology Data Exchange (ETDEWEB)

    Baeuchle, Bjoern [Frankfurt Institute for Advanced Studies (FIAS), Ruth-Moufang-Str. 1, D-60438 Frankfurt am Main (Germany); Bleicher, Marcus; Grimm, Andreas [Frankfurt Institute for Advanced Studies (FIAS), Ruth-Moufang-Str. 1, D-60438 Frankfurt am Main (Germany); Frankfurt Univ. (Germany). Inst. fuer Theoretische Physik

    2013-07-01

    Photons, as all electromagnetic probes, can give direct access to the hot and dense phase of a heavy-ion reaction. We show calculations of direct photon emission at SiS100- and SiS-300 energies with the UrQMD-hybrid model. UrQMD is a full microscopic+macroscopic transport/fluid-dynamics hybrid model with hadron- and string-driven equilibration phase, a full (3+1)-dimensional fluiddynamic hot and dense phase and a hadronic after-burner. Unequilibrated matter at high rapidity is preserved during the fluid phase. A strong emphasis is set on the impact of viscosity and Equation of State at zero and non-zero baryon density to the spectra and flow patterns of thermal and non-thermal photons in A+A-collisions at the colliding systems relevant for FAIR.

  9. Obesity, paternalism and fairness.

    Science.gov (United States)

    Kniess, Johannes

    2015-11-01

    Many liberal theories are committed to the promotion of population health, and the principle of non-interference in individual life plans. Public health interventions often bring out a tension between these two values. In this paper, I examine this tension by assessing the justifiability of liberty-restricting policies in the field of obesity prevention. As I want to show, a 'soft' form of paternalism, which interferes with people's choices to safeguard their true interests, goes some way in justifying such policies, but it leaves unaddressed the problem of limiting the liberty of those whose true interest is in pursuing an unhealthy lifestyle. I argue that in this latter case, the key to reconcile the promotion of population health with the respect for individual liberty is distributive justice: when we cannot help those who care about their health without doing the same for those who do not, fairness will often require us to do so.

  10. Hydrodynamic Drag on Streamlined Projectiles and Cavities

    KAUST Repository

    Jetly, Aditya

    2016-04-19

    The air cavity formation resulting from the water-entry of solid objects has been the subject of extensive research due to its application in various fields such as biology, marine vehicles, sports and oil and gas industries. Recently we demonstrated that at certain conditions following the closing of the air cavity formed by the initial impact of a superhydrophobic sphere on a free water surface a stable streamlined shape air cavity can remain attached to the sphere. The formation of superhydrophobic sphere and attached air cavity reaches a steady state during the free fall. In this thesis we further explore this novel phenomenon to quantify the drag on streamlined shape cavities. The drag on the sphere-cavity formation is then compared with the drag on solid projectile which were designed to have self-similar shape to that of the cavity. The solid projectiles of adjustable weight were produced using 3D printing technique. In a set of experiments on the free fall of projectile we determined the variation of projectiles drag coefficient as a function of the projectiles length to diameter ratio and the projectiles specific weight, covering a range of intermediate Reynolds number, Re ~ 104 – 105 which are characteristic for our streamlined cavity experiments. Parallel free fall experiment with sphere attached streamlined air cavity and projectile of the same shape and effective weight clearly demonstrated the drag reduction effect due to the stress-free boundary condition at cavity liquid interface. The streamlined cavity experiments can be used as the upper bound estimate of the drag reduction by air layers naturally sustained on superhydrophobic surfaces in contact with water. In the final part of the thesis we design an experiment to test the drag reduction capacity of robust superhydrophobic coatings deposited on the surface of various model vessels.

  11. Robust Energy Hub Management Using Information Gap Decision Theory

    DEFF Research Database (Denmark)

    Javadi, Mohammad Sadegh; Anvari-Moghaddam, Amjad; Guerrero, Josep M.

    2017-01-01

    tools in order to deal with uncertainties and to provide reliable operating conditions. On a broader scale, an energy hub includes diverse energy sources for supplying both electrical load and heating/cooling demands with stochastic behaviors. Therefore, this paper utilizes the Information Decision Gap...... Theory (IGDT) to tackle this uncertainty as an efficient robust optimization tool with low complexity to ensure the optimal operation of the system according to the priorities of the decision maker entity. The proposed optimization framework is also implemented on a benchmark energy hub which includes...

  12. Variable volume combustor with center hub fuel staging

    Energy Technology Data Exchange (ETDEWEB)

    Ostebee, Heath Michael; McConnaughhay, Johnie Franklin; Stewart, Jason Thurman; Keener, Christopher Paul

    2016-08-23

    The present application and the resultant patent provide a combustor for use with a gas turbine engine. The combustor may include a number of micro-mixer fuel nozzles and a fuel injection system for providing a flow of fuel to the micro-mixer fuel nozzles. The fuel injection system may include a center hub for providing the flow of fuel therethrough. The center hub may include a first supply circuit for a first micro-mixer fuel nozzle and a second supply circuit for a second micro-mixer fuel nozzle.

  13. Bus coordination holding control for transit hubs under APTS

    Institute of Scientific and Technical Information of China (English)

    TENG Jing; ZHAO Ming

    2009-01-01

    To increase the passenger transferring efficiency, the bus coordination holding control for transit hubs,hich is as an important dynamic dispatching method for improving the service level of transit hubs, was studied in the framework of bus coordination dispatching mode. Firstly, the bus coordination holding control flow was studied based on Advanced Public Transportation Systems (APTS) environment. Then a control model was presented to optimize the bus vehicle holding time, and a genetic algorithm was designed as the solving method. In the end, an example was given to illustrate the effectiveness of the control strategy and the algorithm.

  14. Fairness ja tak - men hvordan?

    DEFF Research Database (Denmark)

    Lyngbye, Lise

    2008-01-01

    Journalistik skal være fair - vi hører og læser det igen og igen i skåltaler og debatindlæg. Men hvad betyder det lille ord fair egentlig, når vi snakker journalistik? Er det en floskel at hævde, at journalistik skal være fair? Eller ligger der gemt i ordet nole journalistiske dyder, som vi skal...

  15. Static torque and drag characteristics of an S-shaped Savonius rotor and prediction of dynamic characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Sadrul Islam, A.K.M.; Quamrul Islam, M.; Razzaque, M.M. [Bangladesh University (Bangladesh). Dept. of Mechanical Engineering; Ashref, R

    1995-12-31

    Drag and torque coefficients of a stationary S-shaped rotor have been investigated by measuring the pressure distribution on the blade surfaces for various rotor angles. The experiments have been carried out at a Reynolds number of 1.1 x 10{sup 5} in a uniform flow jet produced by an open circuit wind tunnel. The measurements indicate that the drag force, and hence the torque, varies with rotor angle. The maximum net static torque occurs at 45{sup o} of rotor angle and it becomes negative in the range of 135{sup o} to 165{sup o} of rotor angle. A quasi-steady approach has been applied for the prediction of the dynamic performance of the rotor using the static drag and torque coefficients. This method results in a fair agreement with the measured power coefficient. (Author)

  16. Solute drag on perfect and extended dislocations

    Science.gov (United States)

    Sills, R. B.; Cai, W.

    2016-04-01

    The drag force exerted on a moving dislocation by a field of mobile solutes is studied in the steady state. The drag force is numerically calculated as a function of the dislocation velocity for both perfect and extended dislocations. The sensitivity of the non-dimensionalized force-velocity curve to the various controlling parameters is assessed, and an approximate analytical force-velocity expression is given. A non-dimensional parameter S characterizing the strength of the solute-dislocation interaction, the background solute fraction ?, and the dislocation character angle ?, are found to have the strongest influence on the force-velocity curve. Within the model considered here, a perfect screw dislocation experiences no solute drag, but an extended screw dislocation experiences a non-zero drag force that is about 10 to 30% of the drag on an extended edge dislocation. The solutes can change the spacing between the Shockley partials in both stationary and moving extended dislocations, even when the stacking fault energy remains unaltered. Under certain conditions, the solutes destabilize an extended dislocation by either collapsing it into a perfect dislocation or causing the partials to separate unboundedly. It is proposed that the latter instability may lead to the formation of large faulted areas and deformation twins in low stacking fault energy materials containing solutes, consistent with experimental observations of copper and stainless steel containing hydrogen.

  17. Lift and Drag Measurements of Superhydrophobic Hydrofoils

    Science.gov (United States)

    Sur, Samrat; Kim, Jeong-Hyun; Rothstein, Jonathan

    2015-11-01

    For several years, superhydrophobic surfaces which are chemically hydrophobic with micron or nanometer scale surface features have been considered for their ability to reduce drag and produce slip in microfluidic devices. More recently it has been demonstrated that superhydrophobic surfaces reduce friction coefficient in turbulent flows as well. In this talk, we will consider that modifying a hydrofoil's surface to make it superhydrophobic has on the resulting lift and drag measurements over a wide range of angles of attack. Experiments are conducted over the range of Reynolds numbers between 10,000hydrofoil is made superhydrophobic. The hydrofoils are coated Teflon that has been hot embossed with a 325grit stainless steel woven mesh to produce a regular pattern of microposts. In addition to fully superhydrophobic hydrofoils, selectively coated symmetrical hydrofoils will also be examined to study the effect that asymmetries in the surface properties can have on lift and drag. Partially funded by NSF CBET-1334962.

  18. Influence of a fairing on the efficiency of a Savonius rotor

    Science.gov (United States)

    Botrini, M.; Chauvin, A.

    An attempt to improve the power coefficient and moment of the Savonius rotor by placing a fairing in front of the upwind-turning convex vane is described. A model was tested in a subsonic wind tunnel using a partially overlapping design, with trials run at 12.5 and 15 m/sec wind velocities using two different fairing configurations, one short and one long. The efficiency was calculated in terms of the free stream wind speed to the speed of the rotor, and it was found that the increase in power converted was sensitive to the length of the fairing. The longer fairing produced higher power coefficients. The ramp was concluded to augment the actual flow entering the rotor, in addition to reducing drag on the upwind-turning rotor.

  19. Portable Desktop Apps with GitHub Electron

    CERN Document Server

    CERN. Geneva

    2016-01-01

    Wouldn't it be nice if you could develop applications that work everywhere, regardless of Operating System or Platform? Even better, what if you could employ the same front-end technologies you use for your web/mobile apps? Meet GitHub Electron.

  20. The evolution of the MasAgro hubs

    NARCIS (Netherlands)

    Camacho-Villa, Tania Carolina; Almekinders, Conny; Hellin, Jon; Martinez-Cruz, Tania Eulalia; Rendon-Medel, Roberto; Guevara-Hernández, Francisco; Beuchelt, Tina D.; Govaerts, Bram

    2016-01-01

    Purpose: Little is known about effective ways to operationalize agricultural innovation processes. We use the MasAgro program in Mexico (which aims to increase maize and wheat productivity, profitability and sustainability), and the experiences of middle level ‘hub managers’, to understand how innov

  1. Native Avatars, Online Hubs, and Urban Indian Literature

    Science.gov (United States)

    Estrada, Gabriel S.

    2011-01-01

    Teaching American Indian literature with online resources can help diverse urban Indian and multicultural students connect with American Indian cultures, histories, and Nations. This online-enriched pedagogy adopts Susan Lobo's sense of the city as an "urban hub," or activist community center, an urban area linked to reservations in which Native…

  2. Fatigue Analysis of Casted Hubs in Wind Turbines

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard; Nielsen, Søren R.K.; Sørensen, Steffen

    2002-01-01

    The hub of a wind turbine rotor is excited by time-varying forces and moments from the blades caused by extemal dynamic loads such as wind loading and aeroelastic effects. The paper describes how reliability-based fatigue analysis can be made based on SN-curves and how reliability-based inspectio...

  3. Functional Connectivity Hubs and Networks in the Awake Marmoset Brain

    Directory of Open Access Journals (Sweden)

    Annabelle Marie Belcher

    2016-03-01

    Full Text Available In combination with advances in analytical methods, resting-state fMRI is allowing unprecedented access to achieve a better understanding of the network organization of the brain. Increasing evidence suggests that this architecture may incorporate highly functionally connected nodes, or hubs, and we have recently proposed local functional connectivity density (lFCD mapping to identify highly-connected nodes in the human brain. Here we imaged awake nonhuman primates to test whether, like the human brain, the marmoset brain contains functional connectivity hubs. Ten adult common marmosets (Callithrix jacchus were acclimated to mild, comfortable restraint using individualized helmets. Following restraint training, resting BOLD data were acquired during eight consecutive 10 min scans for each subject. lFCD revealed prominent cortical and subcortical hubs of connectivity across the marmoset brain; specifically, in primary and secondary visual cortices (V1/V2, higher-order visual association areas (A19M/V6[DM], posterior parietal and posterior cingulate areas (PGM and A23b/A31, thalamus, dorsal and ventral striatal areas (caudate, putamen, lateral septal nucleus, and anterior cingulate cortex (A24a. lFCD hubs were highly connected to widespread areas of the brain, and further revealed significant network-network interactions. These data provide a baseline platform for future investigations in a nonhuman primate model of the brain’s network topology.

  4. The evolution of the MasAgro hubs

    NARCIS (Netherlands)

    Camacho-Villa, Tania Carolina; Almekinders, Conny; Hellin, Jon; Martinez-Cruz, Tania Eulalia; Rendon-Medel, Roberto; Guevara-Hernández, Francisco; Beuchelt, Tina D.; Govaerts, Bram

    2016-01-01

    Purpose: Little is known about effective ways to operationalize agricultural innovation processes. We use the MasAgro program in Mexico (which aims to increase maize and wheat productivity, profitability and sustainability), and the experiences of middle level ‘hub managers’, to understand how

  5. DAVINC3I: moving towards responsive hub network designs

    NARCIS (Netherlands)

    Ossevoort, R.; Keizer, de M.; Vorst, van der J.G.A.J.; Wenink, E.

    2013-01-01

    The Dutch floricultural sector is generally appreciated for its world leadership; the Netherlands is the flower trading hub for the European market. There are two trends affecting this position. First, virtualisation makes trade flows relatively footloose and flexible. Moreover, it enables the use o

  6. Discovering Authorities and Hubs in Different Topological Web Graph Structures.

    Science.gov (United States)

    Meghabghab, George

    2002-01-01

    Discussion of citation analysis on the Web considers Web hyperlinks as a source to analyze citations. Topics include basic graph theory applied to Web pages, including matrices, linear algebra, and Web topology; and hubs and authorities, including a search technique called HITS (Hyperlink Induced Topic Search). (Author/LRW)

  7. DAVINC3I: moving towards responsive hub network designs

    NARCIS (Netherlands)

    Ossevoort, R.; Keizer, de M.; Vorst, van der J.G.A.J.; Wenink, E.

    2013-01-01

    The Dutch floricultural sector is generally appreciated for its world leadership; the Netherlands is the flower trading hub for the European market. There are two trends affecting this position. First, virtualisation makes trade flows relatively footloose and flexible. Moreover, it enables the use o

  8. Interaction of railway and marine transport (Murmansk Transport Hub

    Directory of Open Access Journals (Sweden)

    Sokolov A.A.

    2015-03-01

    Full Text Available The classification of problems of interaction between water (marine and railway transport on the example of the Murmansk Transport Hub has been presented; some prospects for the development of technology for interaction with the logistics of transportation of general cargo in the Murmansk Commercial Seaport, Murmansk Marine Fishing Port, and oil terminals of the Kola Bay have been shown

  9. The Urban Food Hubs Solution: Building Capacity in Urban Communities

    Science.gov (United States)

    O'Hara, Sabine

    2017-01-01

    Access to affordable fresh food is an ongoing challenge for underserved urban neighborhoods across the United States. Several are designated food deserts with no access to a full-service grocery store within a one-mile radius. The Urban Food Hubs of the College of Agriculture, Urban Sustainability, and Environmental Sciences (CAUSES) of the…

  10. Induce Drag Reduction of an Airplane Wing

    Directory of Open Access Journals (Sweden)

    Md. Fazle Rabbi

    2015-06-01

    Full Text Available This work describes the aerodynamic characteristics for aircraft wing model with and without slotted winglet. When an aircraft moves forward with a high speed then a small circulatory motion of air is created at the wingtip due to the pressure difference between the upper and lower surface of the wing is called vortices. This circulatory fluid tends to leak from lower to upper surface of wing which causes downward motion is called “downwash” and generates a component of the local lift force in the direction of the free stream called induced drag. Downwash causes reduction of lift and contribute induced drag to the total drag. Drag reduction for aerial vehicles has a range of positive ramifications: reduced fuel consumption, larger operational range, greater endurance and higher achievable speeds. An experimental study is conducted to examine the potentiality of slotted winglet for the reduction of induced drag, and for the improvement of lift coefficient without increasing the span of aircraft wing. The model composed of a swept wing built from NACA 0012 airfoil. The test conducted in subsonic wind tunnel of 1m×1m rectangular test section at flow speed 25m/s placing the wing without winglet, wing with winglet at 30° inclination, wing with winglet at 60° inclination, and wing with winglet at 70° inclination at angle of attack ranging from 0 to 16 degree. The test result shows 20- 25% reduction in drag coefficient and 10-20% increase in lift coefficient by using slotted winglet.

  11. Canton Fair: Decline, but Optimistic

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    @@ The Canton Fair, long regarded as an important weather vane for China's foreign trade, this year faced bitter, cold winds. Trade volume of main "export products such as machines and light industrial products all saw a decline, although the degree of decline differed in different sectors. The total trade volume in this Canton Fair dropped 16.9% below the previous one.

  12. Affect and fairness in economics

    NARCIS (Netherlands)

    van Winden, F.A.A.M.

    2007-01-01

    A strained relationship exists between mainstream economics and ethics. Over the last decade, behavioral economists have strongly argued for the importance of fairness in motivating behavior, based on substantial experimental evidence. Two main approaches to the modeling of fairness have been

  13. The New Faces of Fairness.

    Science.gov (United States)

    Cole, Nancy S.; Zieky, Michael J.

    2001-01-01

    Proposes additional ways for people in the measurement profession to think about the fairness of assessments and about the fairness of the uses of assessments. Suggests that measurement professionals must pay more attention to reducing group differences at the design stage of test development, to providing all examinees an opportunity to…

  14. Does market competition explain fairness?

    Science.gov (United States)

    Descioli, Peter

    2013-02-01

    The target article by Baumard et al. uses their previous model of bargaining with outside options to explain fairness and other features of human sociality. This theory implies that fairness judgments are determined by supply and demand but humans often perceive prices (divisions of surplus) in competitive markets to be unfair.

  15. Math Fair: Focus on Fractions

    Science.gov (United States)

    Mokashi, Neelima A.

    2009-01-01

    This article depicts the rewarding experience of creating mathematical environments for kindergarten and elementary students by focusing on one of the most important and often difficult-to-grasp concepts (fractions) through play methods incorporated into a math fair. The basic concept of a math fair is threefold: (1) to create preplanned,…

  16. Balancing acts: drag queens, gender and faith.

    Science.gov (United States)

    Sullivan-Blum, Constance R

    2004-01-01

    While engaged in research on the same-sex marriage debate in mainline denominations, I interviewed 23 LGBT Christians, four of whom were drag queens. While it is not possible to generalize from such a small sample, the drag queens in this study insist on maintaining their identity as Christians despite the hegemonic discourse that renders faith and LGBT identities mutually exclusive. They developed innovative approaches to reconciling their gender and sexual identities with their spirituality. Their innovations are potentially liberating not just for them personally, but for LGBT people generally because they challenge Christianity's rigid dichotomies of gender and sexuality.

  17. New drag laws for flapping flight

    Science.gov (United States)

    Agre, Natalie; Zhang, Jun; Ristroph, Leif

    2014-11-01

    Classical aerodynamic theory predicts that a steadily-moving wing experiences fluid forces proportional to the square of its speed. For bird and insect flight, however, there is currently no model for how drag is affected by flapping motions of the wings. By considering simple wings driven to oscillate while progressing through the air, we discover that flapping significantly changes the magnitude of drag and fundamentally alters its scaling with speed. These measurements motivate a new aerodynamic force law that could help to understand the free-flight dynamics, control, and stability of insects and flapping-wing robots.

  18. Trade Fairs, Markets and Fields

    DEFF Research Database (Denmark)

    Moeran, Brian

    2011-01-01

    This article describes how trade fairs act as a framing mechanism that enables participants to come together for the exchange of goods and services and to perceive themselves as acting in a social field. This way, trade fairs make markets possible. Based on ongoing participant observation at book...... fairs in Frankfurt, Tokyo and London, the paper discusses central features of fairs in the light of theoretical categories like networks, institutions and cognitions that are commonly employed in economic sociology. In this context, it highlights that participants negotiate the technical....../material, social, situational, content/appreciative, and the use value of goods, values which are then equated with a commodity exchange value in the form of price. Trade fairs frame order, but they are also events where the respective field might be reconfigurated. The contingency of personal interaction...

  19. Multiple Hub Network Choice in the Liberalized European Market

    Science.gov (United States)

    Berechman, Joseph; deWit, Jaap

    1997-01-01

    A key question that so far has received relatively little attention in the germane literature is that of the changes at various airports as a result of the EU liberalization policies. That is, presently, most major European airports still benefit from the so-called home-carrier phenomenon where the country's publicly or semi-publicly owned carrier uses the country's main airport as its gateway hub and, consequently, the home-carrier is also the principal user of this airport (in terms of proportion of total aircraft movements, number of passengers transported, connections, slots ownership, etc.). The country's main airport has substantially benefited from these monopoly conditions of airline captivity, strongly determined by the bilateral system of international air transport regulation. Therefore, European major airports were used to operate in essentially different markets, compared to the increasingly competitive markets of their home based carriers. This partly explains relative stability of transport volumes and financial results of European major airports compared to the relatively volatile financial results of most European national airlines. However, the liberalization of European aviation is likely to change this situation. Market access is open now to all community carriers, i.e. carriers with majority ownership and effective control in the hands of EU citizens. Ticket prices are free, governments can only intervene in case of dumping or excessive pricing. A community airline can choose its seat in any of the 15 member states. Licensing procedures are harmonized between member states. In the last few months community carriers have had unrestricted route access within the EU. Most probably this development will be extended to countries inside and outside Europe. Last year the European Commission got the mandate to start negotiations with 10 other European countries. In the meantime the EC has also started negotiations with the USA on so-called soft rights

  20. TAXATION. FAIRNESS. EQUALITY

    Directory of Open Access Journals (Sweden)

    Morar Ioan Dan

    2014-12-01

    of the tax burden between them, depending on how the tax base, depending on the type of taxpayer and according to other criteria. Another coordinated taxation is part of contemporary consumerist polticilor new tax, taxing certain income, especially income individuals is marked by the overall objective of capitalist society, that consumption growth. Fiscal policies are policies the new contemporary consumerism. And this phenomenon influences the distribution of the tax burden among taxpayers, more or less fair. What is tax fairness and how we can quantify? Here's a question that I try to raspunt from equality before the law tax payers. Equality before the tax law is not a primary goal of modern tax policy, it losing ground to tax efficiency goals and its economic and social components. On the other hand though fiscal phenomenon can help to ensure social peace through taxation to keep Sean absolute size of the tax burden and the fact that all are equal before the law, tax law and within given social policies in broadly, social security or insurance in respect restrains can be promoted by themselves and less by fiscal policy.

  1. Judicial civil procedure dragging out in Kosovo

    Directory of Open Access Journals (Sweden)

    Rrustem Qehaja

    2016-03-01

    Full Text Available This article tends to deal with one of the most worrying issues in the judicial system of Kosovo the problem of judicial civil procedure dragging out. The article analyses the reasons of these dragging outs of the judicial civil procedure focusing on the context of one of the basic procedural principles in civil procedure-the principle of economy or efficiency in the courts. Dragging out of civil procedure in Kosovo has put in question not only the basic principles of civil procedure, but it also challenges the general principles related to human rights and freedoms sanctioned not only by the highest legal act of the country, but also with international treaties. The article tends to give a reflection to the most important reasons that effect and influence in these dragging outs of civil procedure, as well as, at the same time aims to give the necessary alternatives to pass through them by identifying dilemmas within the judicial practice. As a result, the motives of this scientific paper are exactly focused at the same time on identifying the dilemmas, as well as presenting ideas, to overstep them, including the judicial practice of the European Court of Human Rights on Article 6 of the European Convention on Human Rights, by which it is given the possibility to offering people efficient and within a reasonable time legal protection of their rights before national courts. For these reasons, the paper elaborates this issue based on both, the legal theory and judicial practice.

  2. ABM Drag_Pass Report Generator

    Science.gov (United States)

    Fisher, Forest; Gladden, Roy; Khanampornpan, Teerapat

    2008-01-01

    dragREPORT software was developed in parallel with abmREPORT, which is described in the preceding article. Both programs were built on the capabilities created during that process. This tool generates a drag_pass report that summarizes vital information from the MRO aerobreaking drag_pass build process to facilitate both sequence reviews and provide a high-level summarization of the sequence for mission management. The script extracts information from the ENV, SSF, FRF, SCMFmax, and OPTG files, presenting them in a single, easy-to-check report providing the majority of parameters needed for cross check and verification as part of the sequence review process. Prior to dragReport, all the needed information was spread across a number of different files, each in a different format. This software is a Perl script that extracts vital summarization information and build-process details from a number of source files into a single, concise report format used to aid the MPST sequence review process and to provide a high-level summarization of the sequence for mission management reference. This software could be adapted for future aerobraking missions to provide similar reports, review and summarization information.

  3. Turbulent drag reduction in dilute polymer solutions

    Science.gov (United States)

    Sreenivasan, K. R.; White, Christopher M.

    1998-11-01

    It is well known that the addition of small amounts of flexible polymers reduces drag in turbulent pipe flows. However, the underlying physics is still poorly understood. This paper will consider two aspects: The dependence of the onset of drag reduction on polymer concentration, and the so-called maximum drag reduction asymptote. The latter defines the maximum drag reduction possible for any polymer at a given Reynolds number, independent of the polymer concentration and detailed polymeric structure [1]. It is shown tentatively that a modest reworking of de Gennes' theory [2] is compatible with available experimental data. The principal element of the theory is that the polymers do not get stretched fully, but that the partially extended polymers store elastic energy and interfere with cascade mechanisms in turbulence. A conclusive understanding requires experiments in which the polymer properties that go into the theory are directly measured. [1] P.S. Virk, AIChE J., 21, 625 (1975) [2] P.G. de Gennes, Introduction to Polymer Dynamics, University of Cambridge (1990)

  4. Wind speed scaling and the drag coefficient

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Wind speed scaling in similarity law in wind-generated waves and the drag coefficient are studied. In analyzing the data in the wind wave channel, it is found that the u. scaling greatly reduces the scatter in the U10 scaling. The u. scaling has much less scatter than the scaling using other wind speeds. The friction velocity seems to play a distinctive role in wave growth. The result is important in the applications of the similarity law and in wave modeling. In theory it gives an insight into the mechanism of wind wave interaction. It is found that wave steepness is important in influencing the drag coefficient. The variability of the coefficients in the currently widely used drag form can be explained by the differences in wave steepness in the observations. A drag coefficient model with wind speed and wave steepness as parameters is proposed. An explanation for Kahma' s result that the u. scaling does not reduce the scatter in the U10 scaling is given.

  5. Drag reduction using slippery liquid infused surfaces

    Science.gov (United States)

    Hultmark, Marcus; Stone, Howard; Smits, Alexander; Jacobi, Ian; Samaha, Mohamed; Wexler, Jason; Shang, Jessica; Rosenberg, Brian; Hellström, Leo; Fan, Yuyang

    2013-11-01

    A new method for passive drag reduction is introduced. A surface treatment inspired by the Nepenthes pitcher plant, previously developed by Wong et al. (2011), is utilized and its design parameters are studied for increased drag reduction and durability. Nano- and micro-structured surfaces infused with a lubricant allow for mobility within the lubricant itself when the surface is exposed to flow. The mobility causes slip at the fluid-fluid interface, which drastically reduces the viscous friction. These new surfaces are fundamentally different from the more conventional superhydrophobic surfaces previously used in drag reduction studies, which rely on a gas-liquid interface. The main advantage of the liquid infused surfaces over the conventional surfaces is that the lubricant adheres more strongly to the surface, decreasing the risk of failure when exposed to turbulence and other high-shear flows. We have shown that these surfaces can reduce viscous drag up to 20% in both Taylor-Couette flow and in a parallel plate rheometer. Supported under ONR Grants N00014-12-1-0875 and N00014-12-1-0962 (program manager Ki-Han Kim).

  6. What Is Fair in the Fair Transport Concept?

    DEFF Research Database (Denmark)

    Borgström, Benedikte

    It starts in a simple question and purpose of what is fair in the transport chain concept, and develops to an abductive reasoning based on critical business ethics research and polyphonic narratives for an understanding of the mess that involves people, ethics in supply chains, interest organizat......It starts in a simple question and purpose of what is fair in the transport chain concept, and develops to an abductive reasoning based on critical business ethics research and polyphonic narratives for an understanding of the mess that involves people, ethics in supply chains, interest......-existence. Fairness in fair transport is suggested to be of a dynamic nature and derived from knowledgeable reasoning and found in lived ethico-political relationships....

  7. Science Fairs: The Whys and Hows.

    Science.gov (United States)

    Edelman, Phyllis

    1988-01-01

    There has been some evidence that students who develop projects for science fairs continue their interest in science through high school and beyond. Local and regional fairs generally are slated as a prelude to state science fairs and the International Science and Engineering Fair (ISEF). Organizing a district science fair requires informed…

  8. Significance of relative velocity in drag force or drag power estimation for a tethered float

    Digital Repository Service at National Institute of Oceanography (India)

    Vethamony, P.; Sastry, J.S.

    There is difference in opinion regarding the use of relative velocity instead of particle velocity alone in the estimation of drag force or power. In the present study, a tethered spherical float which undergoes oscillatory motion in regular waves...

  9. Trade Fairs, Markets and Fields

    DEFF Research Database (Denmark)

    Moeran, Brian

    2011-01-01

    This article describes how trade fairs act as a framing mechanism that enables participants to come together for the exchange of goods and services and to perceive themselves as acting in a social field. This way, trade fairs make markets possible. Based on ongoing participant observation at book....../material, social, situational, content/appreciative, and the use value of goods, values which are then equated with a commodity exchange value in the form of price. Trade fairs frame order, but they are also events where the respective field might be reconfigurated. The contingency of personal interaction...

  10. Fair Value or Market Value?

    Directory of Open Access Journals (Sweden)

    Bogdan Cosmin Gomoi

    2014-12-01

    Full Text Available When taking into consideration the issue of defining the “fair value” concept, those less experimented in the area often fall in the “price trap”, which is considered as an equivalent of the fair value of financial structures. This valuation basis appears as a consequence of the trial to provide an “accurate image” by the financial statements and, also, as an opportunity for the premises offered by the activity continuing principle. The specialized literature generates ample controversies regarding the “fair value” concept and the “market value” concept. The paper aims to debate this issue, taking into account various opinions.

  11. Fair use versus fair return: copyright legislation and its consequences.

    Science.gov (United States)

    Horowitz, I L; Curtis, M E

    1984-03-01

    The purpose of this article is to examine the ramifications of legislative recognition of the concept of fair use in the Copyright Act of 1976. The fair use concept, while of small consequence in its normative origins, has turned out to be the foundation of the most perplexing and divisive issues in the new legislative guidelines governing copyright. Legislative recognition of the concept of fair use, coupled with enormous growth of a new technology--extending from xerography to on-line database systems--creates de facto exemptions to both the intent and content of new copyright guidelines. The issue is not one of limiting use or suppressing information, but of mechanisms for safeguarding the rights of copyright holders, be they authors or publishers, and insuring the free flow of information by providing a proper return on both intellectual creativity and capital expenditures. The authors argue that the elimination, or at least curtailment of fair use doctrine, coupled with an increase in technological approaches to reporting of secondary use of copyrighted material, will benefit all sections of the knowledge industry. Authors will receive proper royalties on use; publishers will be able to sell more books and journals at lower prices; and librarians will be liberated from extensive chores such as monitoring usage or determining fee schedules and transferences. The issue is one of fair return--an issue obscured and ultimately subverted by fair use.

  12. Nacelle drag reduction: An analytically-guided experimental program

    Science.gov (United States)

    Smetana, F. O.

    1975-01-01

    Modifications are proposed to standard estimating procedures, as well as the BODY computer program, which predict that the drag of two nacelles will equal the drag of the fuselage. A preliminary computer analysis that considers increased dimensions for the nacelle forebody so that the noise is relatively less blunt indicates a reduction in form drag much greater than the increase in skin friction drag attributable to increased surface area.

  13. Navier slip model of drag reduction by Leidenfrost vapour layers

    OpenAIRE

    Berry, Joseph D; Vakarelski, Ivan U.; Chan, Derek Y. C.; Thoroddsen, Sigurdur T.

    2016-01-01

    Recent experiments found that a hot solid sphere that is able to sustain a stable Leidenfrost vapour layer in a liquid exhibits significant drag reduction during free fall. The variation of the drag coefficient with Reynolds number shows substantial deviation from the characteristic drag crisis behavior at high Reynolds numbers. Results obtained with liqiuds of different viscosities show that onset of the drag crisis depends on the viscosity ratio of the vapor to the liquid. The key feature o...

  14. Investigation into the Mechanism of Polymer Thread Drag Reduction

    Science.gov (United States)

    1990-01-01

    drag reducers than polyacrylamides of equal molecular weight. The drag reduction increases as the Re or Cm increases. The concentrations of polymer...wall region, 10 < y’ < 100, for drag reduction to occur. The normalized distance from the wall is defined as y* = yut/v; u, is the friction velocity...AP 30, a polyacrylamide solution, with a 5000 ppm concentration on the centerline of a water flow in a glass tube, they achieved drag reduction up to

  15. To what extent Fair Value is Fair, an Analysis of Reliability and Relevance of the Fair Value Accounting Paradigm.

    OpenAIRE

    Dugarte, Rafael

    2006-01-01

    To what extent Fair Value is Fair, an Analysis of Reliability and Relevance of the Fair Value Accounting Paradigm. Rafael Dugarte Escalante September, 2006 Fair value accounting is fair and important for financial reporting in providing relevant, reliable, comparable and understandable information to the users depending on what kind of information is expected from it, and the way in which fair value is actually found. This study complemen...

  16. Final Report for Project: Impacts of stratification and non-equilibrium winds and waves on hub-height winds

    Energy Technology Data Exchange (ETDEWEB)

    Patton, Edward G. [Univ. Corporation for Atmospheric Research, Boulder, CO (United States)

    2015-07-14

    wind plant scale. Overall project conclusions include; In the presence of fast-moving swell (significant wave height Hs = 6.4 m, and phase speed cp = 18 ms-1), the atmospheric boundary layer grows more rapidly when waves propagate opposite to the winds compared to when winds and waves are aligned. Pressure drag increases by nearly a factor of 2 relative to the turbulent stress for the extreme case where waves propagate at 180° compared to the pressure gradient forcing. Net wind speed reduces by nearly 15% at hub-height for the 180°-case compared to the 0°-case, and turbulence intensities increase by nearly a factor of 2. These impacts diminish with decreasing wave age; Stratification increases hub height wind speeds and increases the vertical shear of the mean wind across the rotor plane. Fortuitously, this stability-induced enhanced shear does not influence turbulence intensity at hub height, but does increase (decrease) turbulence intensity below (above) hub height. Increased stability also increases the wave-induced pressure stress by ~ 10%; Off the East Coast of the United States during Coupled Boundary Layers Air-Sea Transfer - Low Wind (CBLAST-Low), cases with short fetch include thin stable boundary layers with depths of only a few tens of meters. In the coastal zone, the relationship between the mean wind and the surface fiction velocity (u*(V )) is significantly related to wind direction for weak winds but is not systematically related to the air sea difference of virtual potential temperature, δθv; since waves generally propagate from the south at the Air-Sea Interaction Tower (ASIT) tower, these results suggest that under weak wind conditions waves likely influence surface stress more than stratification does; and Winds and waves are frequently misaligned in the coastal zone. Stability conditions persist for long duration. Over a four year period, the Forschungsplattformen in Nord- und Ostsee Nr. 1 (FINO1) tower (a site with long fetch

  17. Process fairness, outcome fairness, and dynamic consistency : Experimental evidence for risk and ambiguity

    NARCIS (Netherlands)

    Trautmann, Stefan; van de Kuilen, Gijs

    2016-01-01

    Literature on fairness preferences distinguishes between outcome fairness, concerning the final allocation of payoffs, and process fairness, concerning the expected allocation of payoffs. It is not obvious, however, whether process fairness can consistently be implemented. Once uncertainty is

  18. Octopus-inspired drag cancelation by added mass pumping

    Science.gov (United States)

    Weymouth, Gabriel; Giorgio-Serchi, Francesco

    2016-11-01

    Recent work has shown that when an immersed body suddenly changes its size, such as a deflating octopus during rapid escape jetting, the body experiences large forces due to the variation of added-mass energy. We extend this line of research by investigating a spring-mass oscillator submerged in quiescent fluid subject to periodic changes in its volume. This system isolates the ability of the added-mass thrust to cancel the bluff body resistance (having no jet flow to confuse the analysis) and moves closer to studying how these effects would work in a sustained propulsion case by studying periodic shape-change instead of a "one-shot" escape maneuver. With a combination of analytical, numerical, and experimental results, we show that the recovery of added-mass kinetic energy can be used to completely cancel the drag of the fluid, driving the onset of sustained oscillations with amplitudes as large as four times the average body radius. Moreover, these results are fairly independent of the details of the shape-change kinematics as long as the Stokes number and shape-change number are large. In addition, the effective pumping frequency range based on parametric oscillator analysis is shown to predict large amplitude response region observed in the numerics and experiments.

  19. Phonon-drag effect in FeGa3

    Science.gov (United States)

    Wagner-Reetz, Maik; Kasinathan, Deepa; Schnelle, Walter; Cardoso-Gil, Raul; Rosner, Helge; Grin, Yuri; Gille, Peter

    2014-11-01

    The thermoelectric properties of single-crystalline and polycrystalline FeGa3 are systematically investigated over a wide temperature range. At low temperatures, below 20 K, previously not known pronounced peaks in the thermal conductivity (400 -800 WK-1 m-1) with corresponding maxima in the thermopower (in the order of -16000 μ V K-1) were found in single-crystalline samples. Measurements in single crystals along [100] and [001] directions indicate only a slight anisotropy in both the electrical and thermal transports. From susceptibility and heat-capacity measurements, a magnetic or structural phase transition was excluded. Using density functional theory based calculations, we have revisited the electronic structure of FeGa3 and compared the magnetic (including correlations) and nonmagnetic electronic densities of states. Thermopower at fixed carrier concentrations is calculated using semiclassical Boltzmann transport theory, and the calculated results match fairly with our experimental data. The inclusion of strong electron correlations treated in a mean field manner (by LSDA + U ) does not improve this comparison, rendering strong correlations as the sole explanation for the low-temperature enhancement unlikely. Eventually, after a careful review, we assign the peaks in the thermopower as a manifestation of the phonon-drag effect, which is supported by thermopower measurements in a magnetic field.

  20. 14 CFR 25.697 - Lift and drag devices, controls.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Lift and drag devices, controls. 25.697....697 Lift and drag devices, controls. (a) Each lift device control must be designed so that the pilots....101(d). Lift and drag devices must maintain the selected positions, except for movement produced by an...

  1. 14 CFR 25.699 - Lift and drag device indicator.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Lift and drag device indicator. 25.699....699 Lift and drag device indicator. (a) There must be means to indicate to the pilots the position of each lift or drag device having a separate control in the cockpit to adjust its position. In addition...

  2. Revisiting date and party hubs: novel approaches to role assignment in protein interaction networks.

    Directory of Open Access Journals (Sweden)

    Sumeet Agarwal

    2010-06-01

    Full Text Available The idea of "date" and "party" hubs has been influential in the study of protein-protein interaction networks. Date hubs display low co-expression with their partners, whilst party hubs have high co-expression. It was proposed that party hubs are local coordinators whereas date hubs are global connectors. Here, we show that the reported importance of date hubs to network connectivity can in fact be attributed to a tiny subset of them. Crucially, these few, extremely central, hubs do not display particularly low expression correlation, undermining the idea of a link between this quantity and hub function. The date/party distinction was originally motivated by an approximately bimodal distribution of hub co-expression; we show that this feature is not always robust to methodological changes. Additionally, topological properties of hubs do not in general correlate with co-expression. However, we find significant correlations between interaction centrality and the functional similarity of the interacting proteins. We suggest that thinking in terms of a date/party dichotomy for hubs in protein interaction networks is not meaningful, and it might be more useful to conceive of roles for protein-protein interactions rather than for individual proteins.

  3. SOCIAL ENTREPRENEURSHIP AND FAIR TRADE

    Directory of Open Access Journals (Sweden)

    Dejan Jelovac

    2014-01-01

    Full Text Available In this article we will present different theoretical views and positions on social entrepreneurship, fair trade, buying consumer behaviour and ethical consumerism. The Fair Trade, which is well recognized throughout the world, is an example of good practice of social entrepreneurship. Similarly, globalization processes, the pressure of large corporations, the rapid transmission of information, more and more developed ethical consumer behaviour is clearly contributed to both, the successful development of fair trade and social entrepreneurships. In the empirical part we reviewed and confirmed three of three sets of hypotheses through the quantitative research in Slovenia on sample of 253 respondents. Through the results of our study we also recognized the existence of opportunities for the development of social entrepreneurships in Slovenia. In the discussion and conclusion of the article listed are recommendations for further exploration of ethical consumerism, the development of social entrepreneurship and rising the profile of Fair Trade in Slovenia.

  4. 45 BEACON: 2007 SCIENCE FAIRS

    National Research Council Canada - National Science Library

    Charles R Holliday

    2007-01-01

      CHARLES R. HOLLIDAY 2007 SCIENCE FAIRS The AMS awards Certificates of Outstanding Achievement to student exhibitors for creative scientific endeavor in the areas of atmospheric and related oceanic...

  5. Testing Orions Fairing Separation System

    Science.gov (United States)

    Martinez, Henry; Cloutier, Chris; Lemmon, Heber; Rakes, Daniel; Oldham, Joe; Schlagel, Keith

    2014-01-01

    Traditional fairing systems are designed to fully encapsulate and protect their payload from the harsh ascent environment including acoustic vibrations, aerodynamic forces and heating. The Orion fairing separation system performs this function and more by also sharing approximately half of the vehicle structural load during ascent. This load-share condition through launch and during jettison allows for a substantial increase in mass to orbit. A series of component-level development tests were completed to evaluate and characterize each component within Orion's unique fairing separation system. Two full-scale separation tests were performed to verify system-level functionality and provide verification data. This paper summarizes the fairing spring, Pyramidal Separation Mechanism and forward seal system component-level development tests, system-level separation tests, and lessons learned.

  6. The Economics of Fair Play.

    Science.gov (United States)

    Sigmund, Karl; Fehr, Ernst; Nowak, Martin A.

    2002-01-01

    Reports on the field of experimental economics and speculates about why we value fairness and cooperation over the seemingly more rational selfishness. Illustrates a typical decision making situation using the Ultimatum game. (DDR)

  7. Canton Fair:In Summary

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    @@ The 104th session of China Import and Export Fair was concluded,this session of the fair is being held under the severe conditions that global financial market is experiencing drastic turbulence,financial crisis is spreading to real economy,growth rate of world economy is obviously slowing down with increased uncertainties in international economic environment. Confronted with complicated external environment,in accordance with the arrangement of the leading party group of the Ministry of Commerce,the Canton Fair thoroughly implements the Scientific Outlook on Development by carrying out the significant reform of splitting the fair into three phases. It also achieves positive results and improves organizing capability by serving the transformation of development mode of foreign trade,optimizing the structure for export goods,maintaining the reputation of products made in China,forging Chinese brand,and promoting balanced development of import and export.

  8. Fair Value or Market Value?

    National Research Council Canada - National Science Library

    Bogdan Cosmin Gomoi; Lavinia Denisia Cuc; Robert Almaşi

    2014-01-01

    .... The specialized literature generates ample controversies regarding the “fair value” concept and the “market value” concept. The paper aims to debate this issue, taking into account various opinions.

  9. The 102nd Canton Fair Ends Successfully

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ The 102nd China Import and Export Fair (Canton Fair), one of the major import and export fairs in China offering business people an opportunity to purchase colorful commodities worldwide, concluded successfully on October 30.

  10. Fair Value or Market Value?

    OpenAIRE

    Bogdan Cosmin Gomoi; Lavinia Denisia Cuc; Robert Almaşi

    2014-01-01

    When taking into consideration the issue of defining the “fair value” concept, those less experimented in the area often fall in the “price trap”, which is considered as an equivalent of the fair value of financial structures. This valuation basis appears as a consequence of the trial to provide an “accurate image” by the financial statements and, also, as an opportunity for the premises offered by the activity continuing principle. The specialized literature generates ample controversies reg...

  11. Location of an intermediate hub for port activities

    Science.gov (United States)

    Burciu, Ş.; Ştefănică, C.; Roşca, E.; Dragu, V.; Ruscă, F.

    2015-11-01

    An intermediate hub might increase the accessibility level of ports but also hinterland and so it can be considered more than a facility with a transhipment role. These hubs might lead to the development of other transport services and enhance their role in gathering and covering economic centres within hinterlands and also getting the part of logistic facility for the ports, with effects on port utilization and its connectivity to global economy. A new location for a hub terminal leads to reduced transport distances within hinterland, with decreased transport costs and external effects, so with gains in people's life quality. Because the production and distribution systems are relatively fixed on short and medium term and the location decisions are strategic and on long term, the logistic chains activities location models have to consider the uncertainties regarding the possible future situations. In most models, production costs are considered equal, the location problem reducing itself to a problem that aims to minimize the total transport costs, meaning the transport problem. The main objective of the paper is to locate a hub terminal that links the producers of cereals that are going to be exported by naval transportation with the Romanian fluvial-maritime ports (Galaţi, Brăila). GIS environment can be used to integrate and analyse a great amount of data and has the ability of using functions as location - allocation models necessary both to private and public sector, being able to determine the optimal location for services like factories, warehouses, logistic platforms and other public services.

  12. An environmental transfer hub for multimodal atom probe tomography

    Energy Technology Data Exchange (ETDEWEB)

    Perea, Daniel E.; Gerstl, Stephan S. A.; Chin, Jackson; Hirschi, Blake; Evans, James. E.

    2017-05-02

    Environmental control during transfer between instruments is required for specimens sensitive to air or thermal exposure to prevent morphological or chemical changes. Atom Probe Tomography is an expanding technique but commercial instruments remain limited to loading under ambient conditions. Here we describe a multifunctional environmental transfer hub allowing controlled cryogenic, atmospheric and vacuum transfer between an Atom Probe and other instruments containing separate chambers to allow downstream time-resolved in-situ studies.

  13. The new forging process of a wheel hub drop forging

    Directory of Open Access Journals (Sweden)

    A. Gontarz

    2006-08-01

    Full Text Available Purpose: The main purpose of the research was working out a new flashless forming process of wheel hubforging in three-slide forging press (TSFP. It was assumed that the new process would be more effective thanthe forging processes applied in typical forging machines.Design/methodology/approach: The designing of the new process was based on the simulation by finiteelement method with the assumption of 3D state of strain. Calculations were made mainly for the analysis of thematerial flow kinematics and the process loads parameters. Experimental research were also made determiningthe dependency of clamping load in the function of forming load. On the basis of the analysis, the formingprocess of a wheel hub drop forging on the TSFP was worked out.Findings: The results of research confirmed the possibility of flashless forming process of wheel hub forgingin TSFP with axial cavities. The main parameters limiting the forming processes of wheel hub forgings are:permissible upsetting ratio and reciprocal relation of forming and clamping forces.Research limitations/implications: The further research within the range of determining force parameters fordifferent types of material and schemata of forming in TSFP were considered as purposeful. The works dealingwith analysis of forming processes of different types of products in order to classify drop forgings possible toform in this press will be examined.Practical implications: The comparison of the new forming process with the forging process on hammershowed majority of advantages which include: decrease of time and energy, decrease of drop forging weight andmachining, decrease of material consumption.Originality/value: The new process of wheel hub forging forming with axial cavities was worked out. Theparameters important during designing of forming processes in TSFP were provided. The relations betweenforces of forming tools were also determined.

  14. The home hemodialysis hub: physical infrastructure and integrated governance structure.

    Science.gov (United States)

    Marshall, Mark R; Young, Bessie A; Fox, Sally J; Cleland, Calli J; Walker, Robert J; Masakane, Ikuto; Herold, Aaron M

    2015-04-01

    An effective home hemodialysis program critically depends on adequate hub facilities and support functions and on transparent and accountable organizational processes. The likelihood of optimal service delivery and patient care will be enhanced by fit-for-purpose facilities and implementation of a well-considered governance structure. In this article, we describe the required accommodation and infrastructure for a home hemodialysis program and a generic organizational structure that will support both patient-facing clinical activities and business processes.

  15. Robust design of a polygonal shaft-hub coupling

    Directory of Open Access Journals (Sweden)

    R. Citarella

    2015-10-01

    Full Text Available In this work, the Taguchi method is applied for the optimal choice of design parameter values for a polygonal shaft-hub coupling. The objective is to maximize a performance function, minimizing, at the same time, its sensitivity to noises factors (robust design. The Design of Experiments (DoE is adopted to set up a plan of numerical experiments, whose different configurations are simulated using the Boundary Element Method (BEM

  16. Performance evaluation of interconnected logistics networks confronted to hub disruptions

    OpenAIRE

    2016-01-01

    International audience; This paper investigates performance of interconnected logistics networks confronted to disruptions at hub level. With traditional supply chain network design, companies define and optimize their own logistics networks, resulting in current logistics systems being a set of independent heterogeneous logistics networks. The concept of PI aims to integrate independent logistics networks into a global, open, interconnected system. Prior research has shown that the new organ...

  17. Looking east, looking west: Penang as a knowledge hub

    OpenAIRE

    Gerke, Solvay; Evers, Hans-Dieter

    2012-01-01

    Penang has always been a focal point, absorbing knowledge (and popular culture) from civilizations to the East and West. In modern Penang the pattern of cultural contacts has changed over time. Research institutes and universities in Penang cooperate with foreign partners to produce research papers and reports. Based on an analysis of joint research output, the changing international position of Penang as an emerging research hub will be analysed. The paper will show that international cooper...

  18. A Hub Matrix Theory and Applications to Wireless Communications

    Directory of Open Access Journals (Sweden)

    H. T. Kung

    2007-01-01

    Full Text Available This paper considers communications and network systems whose properties are characterized by the gaps of the leading eigenvalues of AHA for a matrix A. It is shown that a sufficient and necessary condition for a large eigen-gap is that A is a “hub” matrix in the sense that it has dominant columns. Some applications of this hub theory in multiple-input and multiple-output (MIMO wireless systems are presented.

  19. Logistics service sharing in supply hub in industrial park (SHIP)

    OpenAIRE

    Qiu, Xuan; 邱璇

    2013-01-01

    Industrial parks have played an indispensible role in boosting economic and industrial development. However, further development has been impeded by the shortage of land resources and by duplicate investments on common physical assets and services. This thesis proposes the concept of Supply Hub in Industrial Park (SHIP) as a public provider of warehousing and transportation services shared by manufacturing enterprises located within an industrial park. This research investigates four typic...

  20. Idea Exchange Music Hub Hits the Right Note in Community

    Directory of Open Access Journals (Sweden)

    Greg Bester

    2014-06-01

    Full Text Available The Cambridge Libraries and Galleries has made many changes over the last two years, rebranding as Idea Exchange and adding 3D printers, creative spaces and many on-site events. This article focuses on one of the organization’s newest innovations, the addition of a Music Hub, and the challenges of creating a space where members can learn and collaborate musically without disturbing those around them.

  1. Research dedusting efficiency of the inertial hub with adjustable parameters

    Directory of Open Access Journals (Sweden)

    Sharapov Rashid

    2016-01-01

    Full Text Available Production of construction materials every year production increases, thus increasing emissions pollutants into the atmosphere subjected to cleaning. At the enterprises of building materials production equipment becoming outdated both morally and physically exhausted their useful life. Technological design standards in the operation of purification equipment has undergone a number of changes. There are a large number of works devoted to the theory of cyclone separation. They examined calculation method and to determine the minimum size of particles is separated completely from the air stream in a cyclone. In theory, the high efficiency cyclones are relatively small separation of particles from the air stream. The experiments show that certain fractions of full capture occurs from the cyclones and out relatively large particles. Designed dust device hubs. They capture dust particles with low specific density and smaller than 5–10 microns. Rational use of hubs is achieved in the aspiration systems high performance. They are placed in front of or between the filter and the cyclone filter. Hub much reduces the amount of dust-laden air directed onto a thin cleaning. This reduces energy consumption for manufacturing as a whole, as well as, due to a possible decrease in performance fine filters, reducing their initial cost, metal consumption, maintenance costs and reduce the area occupied by them.

  2. Matrix logistics indicators assessment of distributed transport hub

    Directory of Open Access Journals (Sweden)

    Igor Arefyev

    2014-06-01

    Full Text Available Background: The paper is devoted to the distributed transport hub substantiation and assessment. The paper  was an example of the technique and form an array of logistical factors as variables that determine this condition. Experience in organizing multimodal transport showed that the "bottleneck" of transport logistics are items of cargo handling ports, terminals, freight stations and warehouses. At the core of the solution of these problems is the problem of estimating the variables determine the Multi-purpose Hubs. The aim is to develop a method of forming the system of logistical multiplying factors determine the role of each of the types in the technologiacal process of distributed Multi-purpose Hubs. Methods: The assessment model for the formation of Distributed Transport Units  can be based on formal methods to predict the behavior of complex systems engineering complexes. Then one of the approaches to the solution of the problem may be the matrix method of technological factors. Results and conclusions: The proposed methodology of the selection and validation of logistic coefficients has the practical importance in the models development for assessing the condition and behavior of Distributed Transport.

  3. The coffee genome hub: a resource for coffee genomes.

    Science.gov (United States)

    Dereeper, Alexis; Bocs, Stéphanie; Rouard, Mathieu; Guignon, Valentin; Ravel, Sébastien; Tranchant-Dubreuil, Christine; Poncet, Valérie; Garsmeur, Olivier; Lashermes, Philippe; Droc, Gaëtan

    2015-01-01

    The whole genome sequence of Coffea canephora, the perennial diploid species known as Robusta, has been recently released. In the context of the C. canephora genome sequencing project and to support post-genomics efforts, we developed the Coffee Genome Hub (http://coffee-genome.org/), an integrative genome information system that allows centralized access to genomics and genetics data and analysis tools to facilitate translational and applied research in coffee. We provide the complete genome sequence of C. canephora along with gene structure, gene product information, metabolism, gene families, transcriptomics, syntenic blocks, genetic markers and genetic maps. The hub relies on generic software (e.g. GMOD tools) for easy querying, visualizing and downloading research data. It includes a Genome Browser enhanced by a Community Annotation System, enabling the improvement of automatic gene annotation through an annotation editor. In addition, the hub aims at developing interoperability among other existing South Green tools managing coffee data (phylogenomics resources, SNPs) and/or supporting data analyses with the Galaxy workflow manager. © The Author(s) 2014. Published by Oxford University Press on behalf of Nucleic Acids Research.

  4. Spider orientation and hub position in orb webs

    Science.gov (United States)

    Zschokke, Samuel; Nakata, Kensuke

    2010-01-01

    Orb-web building spiders (Araneae: Araneoidea, Uloboridae) can be considered as territorial central place foragers. In territorial central place foragers, the optimal foraging arena is circular, with the forager sitting in its centre. In orb webs, the spider’s orientation (head up or head down) whilst waiting for prey on the hub of its web and the downwards-upwards asymmetry of its running speeds are the probable causes for the observed deviation of the hub from the web’s centre. Here, we present an analytical model and a more refined simulation model to analyse the relationships amongst the spider’s running speeds, its orientation whilst waiting for prey and the vertical asymmetry of orb webs. The results of our models suggest that (a) waiting for prey head down is generally favourable because it allows the spider to reach the prey in its web on average quicker than spiders waiting head up, (b) the downwards-upwards running speed asymmetry, together with the head-down orientation of most spiders, are likely causes for the observed vertical asymmetry of orb webs, (c) waiting head up can be advantageous for spiders whose downwards-upwards running speed asymmetry is small and who experience high prey tumbling rates and (d) spiders waiting head up should place their hub lower than similar spiders waiting head down.

  5. Mapping Multiplex Hubs in Human Functional Brain Networks

    Science.gov (United States)

    De Domenico, Manlio; Sasai, Shuntaro; Arenas, Alex

    2016-01-01

    Typical brain networks consist of many peripheral regions and a few highly central ones, i.e., hubs, playing key functional roles in cerebral inter-regional interactions. Studies have shown that networks, obtained from the analysis of specific frequency components of brain activity, present peculiar architectures with unique profiles of region centrality. However, the identification of hubs in networks built from different frequency bands simultaneously is still a challenging problem, remaining largely unexplored. Here we identify each frequency component with one layer of a multiplex network and face this challenge by exploiting the recent advances in the analysis of multiplex topologies. First, we show that each frequency band carries unique topological information, fundamental to accurately model brain functional networks. We then demonstrate that hubs in the multiplex network, in general different from those ones obtained after discarding or aggregating the measured signals as usual, provide a more accurate map of brain's most important functional regions, allowing to distinguish between healthy and schizophrenic populations better than conventional network approaches. PMID:27471443

  6. Innovative Flow Control Concepts for Drag Reduction

    Science.gov (United States)

    Lin, John C.; Whalen, Edward A.; Eppink, Jenna L.; Siochi, Emilie J.; Alexander, Michael G.; Andino, Marlyn Y.

    2016-01-01

    This paper highlights the technology development of two flow control concepts for aircraft drag reduction. The NASA Environmentally Responsible Aviation (ERA) project worked with Boeing to demonstrate these two concepts on a specially outfitted Boeing 757 ecoDemonstrator during the spring of 2015. The first flow control concept used Active Flow Control (AFC) to delay flow separation on a highly deflected rudder and increase the side force that it generates. This may enable a smaller vertical tail to provide the control authority needed in the event of an engine failure during takeoff and landing, while still operating in a conventional manner over the rest of the flight envelope. Thirty-one sweeping jet AFC actuators were installed and successfully flight-tested on the vertical tail of the 757 ecoDemonstrator. Pilot feedback, flow cone visualization, and analysis of the flight test data confirmed that the AFC is effective, as a smoother flight and enhanced rudder control authority were reported. The second flow control concept is the Insect Accretion Mitigation (IAM) innovation where surfaces were engineered to mitigate insect residue adhesion on a wing's leading edge. This is necessary because something as small as an insect residue on the leading edge of a laminar flow wing design can cause turbulent wedges that interrupt laminar flow, resulting in an increase in drag and fuel use. Several non-stick coatings were developed by NASA and applied to panels that were mounted on the leading edge of the wing of the 757 ecoDemonstrator. The performance of the coated surfaces was measured and validated by the reduction in the number of bug adhesions relative to uncoated control panels flown simultaneously. Both flow control concepts (i.e., sweeping jet actuators and non-stick coatings) for drag reduction were the culmination of several years of development, from wind tunnel tests to flight tests, and produced valuable data for the advancement of modern aircraft designs

  7. A Real-Time Web Services Hub to Improve Situation Awareness during Flash Flood Events

    Science.gov (United States)

    Salas, F. R.; Liu, F.; Maidment, D. R.; Hodges, B. R.

    2011-12-01

    The central Texas corridor is one of the most flash flood-prone regions in the United States. Over the years, flash floods have resulted in hundreds of flood fatalities and billions of dollars in property damage. In order to mitigate risk to residents and infrastructure during flood events, both citizens and emergency responders need to exhibit proactive behavior instead of reactive. Real-time and forecasted flood information is fairly limited and hard to come by at varying spatial scales. The University of Texas at Austin has collaborated with IBM Research-Austin and ESRI to build a distributed real-time flood information system through a framework that leverages large scale data management and distribution, Open Geospatial Consortium standardized web services, and smart map applications. Within this paradigm, observed precipitation data encoded in WaterML is ingested into HEC-HMS and then delivered to a high performance hydraulic routing software package developed by IBM that utilizes the latest advancements in VLSI design, numerical linear algebra and numerical integration techniques on contemporary multicore architecture to solve fully dynamic Saint Venant equations at both small and large scales. In this paper we present a real-time flood inundation map application that in conjunction with a web services Hub, seamlessly integrates hydrologic information available through both public and private data services, model services and mapping services. As a case study for this project, we demonstrate how this system has been implemented in the City of Austin, Texas.

  8. Research on Drag Torque Prediction Model for the Wet Clutches

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Considering the surface tension effect and centrifugal effect, a mathematical model based on Reynolds equation for predicting the drag torque of disengage wet clutches is presented. The model indicates that the equivalent radius is a function of clutch speed and flow rate. The drag torque achieves its peak at a critical speed. Above this speed, drag torque drops due to the shrinking of the oil film. The model also points out that viscosity and flow rate effects on drag torque. Experimental results indicate that the model is reasonable and it performs well for predicting the drag torque peak.

  9. Virtual Hubs for facilitating access to Open Data

    Science.gov (United States)

    Mazzetti, Paolo; Latre, Miguel Á.; Ernst, Julia; Brumana, Raffaella; Brauman, Stefan; Nativi, Stefano

    2015-04-01

    In October 2014 the ENERGIC-OD (European NEtwork for Redistributing Geospatial Information to user Communities - Open Data) project, funded by the European Union under the Competitiveness and Innovation framework Programme (CIP), has started. In response to the EU call, the general objective of the project is to "facilitate the use of open (freely available) geographic data from different sources for the creation of innovative applications and services through the creation of Virtual Hubs". In ENERGIC-OD, Virtual Hubs are conceived as information systems supporting the full life cycle of Open Data: publishing, discovery and access. They facilitate the use of Open Data by lowering and possibly removing the main barriers which hampers geo-information (GI) usage by end-users and application developers. Data and data services heterogeneity is recognized as one of the major barriers to Open Data (re-)use. It imposes end-users and developers to spend a lot of effort in accessing different infrastructures and harmonizing datasets. Such heterogeneity cannot be completely removed through the adoption of standard specifications for service interfaces, metadata and data models, since different infrastructures adopt different standards to answer to specific challenges and to address specific use-cases. Thus, beyond a certain extent, heterogeneity is irreducible especially in interdisciplinary contexts. ENERGIC-OD Virtual Hubs address heterogeneity adopting a mediation and brokering approach: specific components (brokers) are dedicated to harmonize service interfaces, metadata and data models, enabling seamless discovery and access to heterogeneous infrastructures and datasets. As an innovation project, ENERGIC-OD will integrate several existing technologies to implement Virtual Hubs as single points of access to geospatial datasets provided by new or existing platforms and infrastructures, including INSPIRE-compliant systems and Copernicus services. ENERGIC OD will deploy a

  10. The other optimal Stokes drag profile

    CERN Document Server

    Montenegro-Johnson, Thomas D

    2014-01-01

    The lowest drag shape of fixed volume in Stokes flow has been known for some 40 years. It is front-back symmetric and similar to an American football with ends tangent to a cone of 60 degrees. The analogous convex axisymmetric shape of fixed surface area, which may be of interest for particle design in chemistry and colloidal science, is characterized in this paper. This "other" optimal shape has a surface vorticity proportional to the mean surface curvature, which is used with a local analysis of the flow near the tip to show that the front and rear ends are tangent to a cone of angle 30.8 degrees. Using the boundary element method, we numerically represent the shape by expanding its tangent angle in terms decaying odd Legendre modes, and show that it has 11.3% lower drag than a sphere of equal surface area, significantly more pronounced than for the fixed-volume optimal.

  11. Frictional Coulomb drag in strong magnetic fields

    DEFF Research Database (Denmark)

    Bønsager, Martin Christian; Flensberg, Karsten; Hu, Ben Yu-Kuang;

    1997-01-01

    A treatment of frictional Coulomb drag between two two-dimensional electron layers in a strong perpendicular magnetic field, within the independent electron picture, is presented. Assuming fully resolved Landau levels, the linear response theory expression for the transresistivity rho(21) is eval......A treatment of frictional Coulomb drag between two two-dimensional electron layers in a strong perpendicular magnetic field, within the independent electron picture, is presented. Assuming fully resolved Landau levels, the linear response theory expression for the transresistivity rho(21......) is evaluated using diagrammatic techniques. The transresistivity is given by an integral over energy and momentum transfer weighted by the product of the screened interlayer interaction and the phase space for scattering events. We demonstrate, by a numerical analysis of the transresistivity, that for well...

  12. Drag Reduction by Polymeric and Nonpolymeric Additives

    Science.gov (United States)

    White, Christopher; Sreenivasan, K. R.

    1997-11-01

    To investigate the ``self-healing'' property of drag reducing surfactant micelles we have conducted a comparative study between high polymers and surfactants in six turbulent pipe flows (Reynolds numbers between 2000 and 90,000) with varying intensities o f secondary flow. Friction factor values are measured in a straight pipe of 185 diameters; three pipes, each turning through four 90 degree elbows, of lengths 1085 diameters, 875 diameters, and 600 diameters; and a twice-turned coiled pipe, radius of curv ature of 24 diameters and length of 290 diameters. All the flows are gravity driven to prevent degradation effects caused by pump impellers. The large stresses set up by the secondary flows degrade the fragile polymers, thus reducing their effectivness as a drag reducer. The ``self-healing'' of the micelles enables the surfactant to maintain its effectivness. We will present the ``self-healing'' characteristics of the surfactant micelles using the polymer data as the datum.

  13. Investigation on Drag Reduction of Trucks

    Institute of Scientific and Technical Information of China (English)

    QI Xiao-ni; LIU Zhen-yan

    2008-01-01

    A study of the mechanism of fences was given to reduce drag by means of theoretical analysis, numerical simulation and experimental research. A 3D mathematical model has been developed based on computational fluid dynamics software Phoenics that was capable of handling steady state, 3D flow to simulate the flow field around the truck. The experiment made in a low speed wind tunnel is used as references for validation. By analyzing the results of calculation and experiment, the flowing mechanism of the flow field around the container truck and the drag-reducing mechanism of #-shaped fences on the truck are unveiled, which provides theoretical guidance to the aerodynamic formation designing and amelioration.

  14. A Note on Disk Drag Dynamics

    CERN Document Server

    Gunther, Neil J

    2012-01-01

    The electrical power consumed by typical magnetic hard disk drives (HDD) not only increases linearly with the number of spindles but, more significantly, it increases as very fast power-laws of speed (RPM) and diameter. Since the theoretical basis for this relationship is neither well-known nor readily accessible in the literature, we show how these exponents arise from aerodynamic disk drag and discuss their import for green storage capacity planning.

  15. Satellite Formation Control Using Atmospheric Drag

    Science.gov (United States)

    2007-03-01

    all cases tested, and the eccentricity-minimizing control law was able to maintain the position within 4.17 feet. More recently, Wedekind considered...three different formations, in-plane, in-track, and circular, was considered. Wedekind achieved favorable results for these three formations when the...and Kluwer Academic Publishers, 2004. 23. Wedekind , James T. Characterizing and Controlling the Effects of Differential Drag on Satellite Formations

  16. Drag Reduction, from Bending to Pruning

    CERN Document Server

    Lopez, Diego; Michelin, Sébastien; de Langre, Emmanuel

    2013-01-01

    Most plants and benthic organisms have evolved efficient reconfiguration mechanisms to resist flow-induced loads. These mechanisms can be divided into bending, in which plants reduce their sail area through elastic deformation, and pruning, in which the loads are decreased through partial breakage of the structure. In this work, we show by using idealized models that these two mechanisms or, in fact, any combination of the two, are equally efficient to reduce the drag experienced by terrestrial and aquatic vegetation.

  17. Satellite Attitude Control Using Atmospheric Drag

    Science.gov (United States)

    2007-03-01

    Astronautics Graduate School of Engineering and Management Air Force Institute of Technology Air University Air Education and Training Command In...yaw axes and provide magnetic damping on both the pitch and yaw axes. The satellite resem- bles a shuttlecock used in badminton (see Figure 2.2). The...Control Using Atmospheric Drag Guettler, David B., Captain, USAF Air Force Institute of Technology Graduate School of Engineering and Management (AFIT

  18. Phonon-drag effects on thermoelectric power

    OpenAIRE

    Wu, M. W.; Horing, N. J. M.; Cui, H. L.

    1995-01-01

    We carry out a calculation of the phonon-drag contribution $S_g$ to the thermoelectric power of bulk semiconductors and quantum well structures for the first time using the balance equation transport theory extended to the weakly nonuniform systems. Introducing wavevector and phonon-mode dependent relaxation times due to phonon-phonon interactions, the formula obtained can be used not only at low temperatures where the phonon mean free path is determined by boundary scattering, but also at hi...

  19. Stokes’ and Lamb's viscous drag laws

    Science.gov (United States)

    Eames, I.; Klettner, C. A.

    2017-03-01

    Since Galileo used his pulse to measure the time period of a swinging chandelier in the 17th century, pendulums have fascinated scientists. It was not until Stokes' (1851 Camb. Phil. Soc. 9 8-106) (whose interest was spurred by the pendulur time pieces of the mid 19th century) treatise on viscous flow that a theoretical framework for the drag on a sphere at low Reynolds number was laid down. Stokes' famous drag law has been used to determine two fundamental physical constants—the charge on an electron and Avogadro's constant—and has been used in theories which have won three Nobel prizes. Considering its illustrious history it is then not surprising that the flow past a sphere and its two-dimensional analog, the flow past a cylinder, form the starting point of teaching flow past a rigid body in undergraduate level fluid mechanics courses. Usually starting with the two-dimensional potential flow past a cylinder, students progress to the three-dimensional potential flow past a sphere. However, when the viscous flow past rigid bodies is taught, the three-dimensional example of a sphere is first introduced, and followed by (but not often), the two-dimensional viscous flow past a cylinder. The reason why viscous flow past a cylinder is generally not taught is because it is usually explained from an asymptotic analysis perspective. In fact, this added mathematical complexity is why the drag on a cylinder was only solved in 1911, 60 years after the drag on a sphere. In this note, we show that the viscous flow past a cylinder can be explained without the need to introduce any asymptotic analysis while still capturing all the physical insight of this classic fluid mechanics problem.

  20. Space Age Swimsuit Reduces Drag, Breaks Records

    Science.gov (United States)

    2008-01-01

    A space shuttle and a competitive swimmer have a lot more in common than people might realize: Among other forces, both have to contend with the slowing influence of drag. NASA s Aeronautics Research Mission Directorate focuses primarily on improving flight efficiency and generally on fluid dynamics, especially the forces of pressure and viscous drag, which are the same for bodies moving through air as for bodies moving through water. Viscous drag is the force of friction that slows down a moving object through a substance, like air or water. NASA uses wind tunnels for fluid dynamics research, studying the forces of friction in gasses and liquids. Pressure forces, according to Langley Research Center s Stephen Wilkinson, dictate the optimal shape and performance of an airplane or other aero/hydro-dynamic body. In both high-speed flight and swimming, says Wilkinson, a thin boundary layer of reduced velocity fluid surrounds the moving body; this layer is about 2 centimeters thick for a swimmer.

  1. Modelling LARES temperature distribution and thermal drag

    CERN Document Server

    Nguyen, Phuc H

    2015-01-01

    The LARES satellite, a laser-ranged space experiment to contribute to geophysics observation, and to measure the general relatistic Lense-Thirring effect, has been observed to undergo an anomalous along-track orbital acceleration of -$0.4\\ pm/s^2$ (pm := picometer). This "drag" is not surprising; along track drag has previously been observed with the related LAGEOS satellites (-$3.4\\ pm/s^2$). It is hypothesized that the drag is due to anisotropic thermal radiation from the satellite's exterior. We report the results of numerical computations of the along-track orbital decay of the LARES satellite during the first 105 days after launch. The results depend to a significant degree on the visual and IR absorbance $\\alpha$ and emissivity $\\epsilon$ of the fused silica cube-cornered laser retroreflectors (CCRs). We present results for two values of $\\alpha_{IR}$ = $\\epsilon_{IR}$: 0.82, a standard number for "clean" fused silica; and 0.60, a possible value for silica with slight surface contamination subjected to ...

  2. Picosecond response of a photon drag detector

    Energy Technology Data Exchange (ETDEWEB)

    Kimmitt, M.F. [Univ. of Essex (United Kingdom)

    1995-12-31

    The primary use of photon drag detectors has been with CO{sub 2} lasers at 10{mu}m. Cornmercially-available devices are limited to response times of < 0.5-1ns and voltage responsivities of <0.5{mu}V W{sup -1}. This poster paper will describe the first photon drag detector specifically designed for very fast response. Using the free-election laser FELIX at the FOM Institute in the Netherlands, a rise time of <50ps has been demonstrated, using a 5mm{sup 2} area detector with a responsivity of >1{mu}V W{sup -1} over the wavelength range 10-25{mu}m. The figure shows the clear resolution of the micropulse structure of the laser. The actual width of each pulse is a few picosecoods, with a micropulse spacing of Ins. The advantages or photon drag detectors are room-temperature operation, linear response to intensifies greater than 10{sup 6}MW cm{sup -2} and very high damage threshold. These detectors are cheap to manufacture and, using different semiconductors, can be designed for any wavelength from 1 {mu}m-5mm.

  3. PREFACE: FAIRNESS 2014: FAIR Next Generation ScientistS 2014

    Science.gov (United States)

    2015-04-01

    FAIRNESS 2014 was the third edition in a series of workshops designed to bring together excellent international young scientists with research interests focused on physics at FAIR (Facility for Antiproton and Ion Research) and was held on September 22-27 2014 in Vietri sul Mare, Italy. The topics of the workshops cover a wide range of aspects in both theoretical developments and current experimental status, concentrated around the four scientific pillars of FAIR. FAIR is a new accelerator complex with brand new experimental facilities, that is currently being built next to the existing GSI Helmholtzzentrum for Schwerionenforschung close to Darmstadt, Germany. The spirit of the conference is to bring together young scientists, e.g. advanced PhD students and postdocs and young researchers without permanent position to present their work, to foster active informal discussions and build up of networks. Every participant in the meeting with the exception of the organizers gives an oral presentation, and all sessions are followed by an hour long discussion period. During the talks, questions are anonymously collected in a box to stimulate discussions. The broad physics program at FAIR is reflected in the wide range of topics covered by the workshop: • Physics of hot and dense nuclear matter, QCD phase transitions and critical point • Nuclear structure, astrophysics and reactions • Hadron Spectroscopy, Hadrons in matter and Hypernuclei • New developments in atomic and plasma physics • Special emphasis is put on the experiments CBM, HADES, PANDA, NUSTAR, APPA and related experiments For each of these different areas one invited speaker was selected to give a longer introductory presentation. The write-ups of the talks presented at FAIRNESS 2014 are the content of this issue of Journal of Physics: Conference Series and have been refereed according to the IOP standard for peer review. This issue constitutes therefore a collection of the forefront of research that

  4. Contextual Hub Analysis Tool (CHAT: A Cytoscape app for identifying contextually relevant hubs in biological networks [version 2; referees: 2 approved

    Directory of Open Access Journals (Sweden)

    Tanja Muetze

    2016-08-01

    Full Text Available Highly connected nodes (hubs in biological networks are topologically important to the structure of the network and have also been shown to be preferentially associated with a range of phenotypes of interest. The relative importance of a hub node, however, can change depending on the biological context. Here, we report a Cytoscape app, the Contextual Hub Analysis Tool (CHAT, which enables users to easily construct and visualize a network of interactions from a gene or protein list of interest, integrate contextual information, such as gene expression or mass spectrometry data, and identify hub nodes that are more highly connected to contextual nodes (e.g. genes or proteins that are differentially expressed than expected by chance. In a case study, we use CHAT to construct a network of genes that are differentially expressed in Dengue fever, a viral infection. CHAT was used to identify and compare contextual and degree-based hubs in this network. The top 20 degree-based hubs were enriched in pathways related to the cell cycle and cancer, which is likely due to the fact that proteins involved in these processes tend to be highly connected in general. In comparison, the top 20 contextual hubs were enriched in pathways commonly observed in a viral infection including pathways related to the immune response to viral infection. This analysis shows that such contextual hubs are considerably more biologically relevant than degree-based hubs and that analyses which rely on the identification of hubs solely based on their connectivity may be biased towards nodes that are highly connected in general rather than in the specific context of interest.   Availability: CHAT is available for Cytoscape 3.0+ and can be installed via the Cytoscape App Store (http://apps.cytoscape.org/apps/chat.

  5. Effects of Polymer Parameters on Drag Reduction.

    Science.gov (United States)

    Safieddine, Abbas Mohammad

    The effects of polymer parameters on fluid drag reduction using polyethylene oxide (PEO), polyacrylamide (PAM), guar gum (GG) and hydroxyethyl cellulose (HEC) were investigated. Due to the unavailability of high molecular weight (MW) water-soluble polymers having narrow molecular weight distribution (MWD), an aqueous preparative size exclusion chromatography (SEC) system capable of fractionating over wide MW ranges was constructed. An online low shear viscometer, coupled to the SEC, measured the instantaneous intrinsic viscosity of the eluting polymer solution and, therefore, served as a MW detector since Mark-Houwink "K" and "a" values for all four polymers were known. With the aid of the viscometer, the SEC system was calibrated. The preparative nature of the chromatography system allowed the collection of large volumes of nearly monodisperse fractions (MWD SEC approach allowed drag reduction (DR) experiments using well-characterized, narrowly dispersed polymer solutions under controlled tube flow conditions. Correlations of drag reduction performance with primary polymer parameters (i.e., concentration, intrinsic viscosity ((eta)), volume fraction (c(eta)), number of chain links (N), and combinations thereof) were used to test the validity of several theoretical DR models. Walsh's energy model, as well as the Deborah argument, did not completely account for drag reduction behavior under all experimental conditions. Within each of the flexible or rigid polymer groups, the extensional viscosity model was successful in correlating c(eta) N with DR under all turbulent conditions. However, it failed to account for the differences in chemical structure between the two polymer groups. However, when the cellulosic repeat unit was used instead of the carbon-carbon bond as the chain link for the rigid polymers (GG and HEC), all DR versus c (eta) N curves under all turbulent conditions collapsed into a single function. This has been predicted by the recent "yo-yo" model of

  6. CERN Scientific Book Fair 2013

    CERN Document Server

    CERN Library

    2013-01-01

    The CERN Bookshop and CERN Library invite you to attend the 2013 CERN Book Fair, a two-day scientific event offering you the opportunity to meet key publishers and to browse and purchase books at significant discounts.   Key publishers will present a selection of titles in physics, technology, mathematics, engineering, computing and popular science. You are welcome to come along and meet the publishers’ representatives or simply have a look at the books on sale. The fair will take place in the Main Building (Bldg. 500) on the ground floor near Restaurant 1 on Monday 9 and Tuesday 10 September. Participating or represented publishers include: Oxford University Press, Princeton University Press, Springer, Wiley, and World Scientific-Imperial College Press. Fair opening times:  - Monday 9 September 9:00 - 18:00  - Tuesday 10 September 9:00 - 18:00

  7. Trade Fairs, Markets and Fields

    DEFF Research Database (Denmark)

    Moeran, Brian

    2011-01-01

    This working paper takes as its starting point the work of the German economic sociologist, Jens Beckert, and his call for empirical investigations into how intentionally rational actors reach decisions under conditions when they do not know what is best to do. It describes how trade fairs act...... as a framing mechanism that enables participants to come together for the exchange of goods and services and to perceive themselves as acting in a social field. Fairs frame the contacts people make and sustain as networks; the institutional rules and social norms guiding their behaviour there; and the values...... and cognitive frames that they bring to bear and negotiate with other participants. They make actors aware of a ‘mutual correspondence’ in their interpretation of the goods in which they deal and of the social situations in which engage for the sake of such trade. Trade fairs both configure fields and make...

  8. Trade Fairs, Markets and Fields

    DEFF Research Database (Denmark)

    Moeran, Brian

    2011-01-01

    This working paper takes as its starting point the work of the German economic sociologist, Jens Beckert, and his call for empirical investigations into how intentionally rational actors reach decisions under conditions when they do not know what is best to do. It describes how trade fairs act...... as a framing mechanism that enables participants to come together for the exchange of goods and services and to perceive themselves as acting in a social field. Fairs frame the contacts people make and sustain as networks; the institutional rules and social norms guiding their behaviour there; and the values...... and cognitive frames that they bring to bear and negotiate with other participants. They make actors aware of a ‘mutual correspondence’ in their interpretation of the goods in which they deal and of the social situations in which engage for the sake of such trade. Trade fairs both configure fields and make...

  9. CERN scientific book fair 2010

    CERN Multimedia

    CERN Library

    2010-01-01

    The CERN Bookshop and CERN Library invite you to attend the 2010 CERN Book Fair, a two-day scientific event offering you the opportunity to meet key publishers and to browse and purchase books at significant discounts.   Some twelve companies will be present and will bring with them a selection of titles in physics, technology, mathematics, engineering, computing and popular science. You are welcome to come along and meet the publishers’ representatives or simply have a look to the books on offer. The Fair will take place in the Main Building (bldg. 500) on the ground floor near the Restaurant 1 on Tuesday 7th and Wednesday 8th September. Participating or represented publishers include: Cambridge University Press, EPFL Press – PPUR, Oxford University Press, Imperial College Press, McGraw-Hill, Oxford University Press, Pearson Education, Princeton University Press, Springer, Taylor and Francis, Wiley, World Scientific. Fair opening times: Tuesday 7 September 9:00 &ndash...

  10. 47 CFR 73.1910 - Fairness Doctrine.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 4 2010-10-01 2010-10-01 false Fairness Doctrine. 73.1910 Section 73.1910... Rules Applicable to All Broadcast Stations § 73.1910 Fairness Doctrine. The Fairness Doctrine is... issues of public importance. See FCC public notice “Fairness Doctrine and the Public Interest Standards...

  11. What's New for the Canton Fair?

    Institute of Scientific and Technical Information of China (English)

    Liu Xinwen

    2008-01-01

    @@ The Canton Fair,one of the top trade fairs in China,has a long history that goes back over 50years.New concerns lie ahead,however,as the senior management of the Canton Fair and the general public look for ways to innovate and improve the fair atmosphere.

  12. The Science Fair Experience: Profile of Science Fair Winners.

    Science.gov (United States)

    Bellipanni, Lawrence J.

    The purpose of this investigation was to determine if a significant relationship existed between the criterion variable of receiving or not receiving awards at the 1993 International Science and Engineering Fair (ISEF) and the predictor variables of resources and facilities, resource personnel, personal costs, time, and personal characteristics.…

  13. Environmental Science: 49 Science Fair Projects. Science Fair Projects Series.

    Science.gov (United States)

    Bonnet, Robert L.; Keen, G. Daniel

    This book contains 49 science fair projects designed for 6th to 9th grade students. Projects are organized by the topics of soil, ecology (projects in habitat and life cycles), pests and controls (projects in weeds and insects), recycling (projects in resources and conservation), waste products (projects in decomposition), microscopic organisms,…

  14. Final Report for Project: Impacts of stratification and non-equilibrium winds and waves on hub-height winds

    Energy Technology Data Exchange (ETDEWEB)

    Patton, Edward G. [Univ. Corporation for Atmospheric Research, Boulder, CO (United States)

    2015-07-14

    wind plant scale. Overall project conclusions include; In the presence of fast-moving swell (significant wave height Hs = 6.4 m, and phase speed cp = 18 ms-1), the atmospheric boundary layer grows more rapidly when waves propagate opposite to the winds compared to when winds and waves are aligned. Pressure drag increases by nearly a factor of 2 relative to the turbulent stress for the extreme case where waves propagate at 180° compared to the pressure gradient forcing. Net wind speed reduces by nearly 15% at hub-height for the 180°-case compared to the 0°-case, and turbulence intensities increase by nearly a factor of 2. These impacts diminish with decreasing wave age; Stratification increases hub height wind speeds and increases the vertical shear of the mean wind across the rotor plane. Fortuitously, this stability-induced enhanced shear does not influence turbulence intensity at hub height, but does increase (decrease) turbulence intensity below (above) hub height. Increased stability also increases the wave-induced pressure stress by ~ 10%; Off the East Coast of the United States during Coupled Boundary Layers Air-Sea Transfer - Low Wind (CBLAST-Low), cases with short fetch include thin stable boundary layers with depths of only a few tens of meters. In the coastal zone, the relationship between the mean wind and the surface fiction velocity (u*(V )) is significantly related to wind direction for weak winds but is not systematically related to the air sea difference of virtual potential temperature, δθv; since waves generally propagate from the south at the Air-Sea Interaction Tower (ASIT) tower, these results suggest that under weak wind conditions waves likely influence surface stress more than stratification does; and Winds and waves are frequently misaligned in the coastal zone. Stability conditions persist for long duration. Over a four year period, the Forschungsplattformen in Nord- und Ostsee Nr. 1 (FINO1) tower (a site with long fetch

  15. Children develop a veil of fairness

    DEFF Research Database (Denmark)

    Shaw, Alex; Montinari, Natalia; Piovesan, Marco

    2014-01-01

    Previous research suggests that children develop an increasing concern with fairness over the course of development. Research with adults suggests that the concern with fairness has at least 2 distinct components: a desire to be fair and a desire to signal to others that they are fair. We explore...... whether children's developing concern with behaving fairly toward others may in part reflect a developing concern with appearing fair to others. In Experiments 1 and 2, most 6- to 8-year-old children behaved fairly toward others when an experimenter was aware of their choices; fewer children opted...... to behave fairly, however, when they could be unfair to others yet appear fair to the experimenter. In Experiment 3, we explored the development of this concern with appearing fair by using a wider age range (6- to 11-year-olds) and a different method. In this experiment, children chose how to assign a good...

  16. An Endosymbiotic Evolutionary Algorithm for the Hub Location-Routing Problem

    Directory of Open Access Journals (Sweden)

    Ji Ung Sun

    2015-01-01

    Full Text Available We consider a capacitated hub location-routing problem (HLRP which combines the hub location problem and multihub vehicle routing decisions. The HLRP not only determines the locations of the capacitated p-hubs within a set of potential hubs but also deals with the routes of the vehicles to meet the demands of customers. This problem is formulated as a 0-1 mixed integer programming model with the objective of the minimum total cost including routing cost, fixed hub cost, and fixed vehicle cost. As the HLRP has impractically demanding for the large sized problems, we develop a solution method based on the endosymbiotic evolutionary algorithm (EEA which solves hub location and vehicle routing problem simultaneously. The performance of the proposed algorithm is examined through a comparative study. The experimental results show that the proposed EEA can be a viable solution method for the supply chain network planning.

  17. The catheter hub disinfection cap as esophageal foreign body.

    Science.gov (United States)

    Tawfik, Kareem O; Myer, Charles M; Shikary, Tasneem; Goldschneider, Kenneth R

    2015-12-01

    Disinfection caps are increasingly being used to prevent catheter-associated bloodstream infections. These devices, designed for continuous passive disinfection of catheter hubs, are typically small and often brightly colored. As such, they have the potential to become pediatric airway and esophageal foreign bodies. We report two patients who developed esophageal foreign body following ingestion of disinfection caps. Given the increasing use of these devices, it is imperative that health care providers be aware of this potential iatrogenic problem. We propose that the use of disinfection caps may not be appropriate in pediatric patients with risk factors for foreign body ingestion.

  18. Wake center position tracking using downstream wind turbine hub loads

    Science.gov (United States)

    Cacciola, S.; Bertelè, M.; Schreiber, J.; Bottasso, C. L.

    2016-09-01

    Having an improved awareness of the flow within a wind farm is useful for power harvesting maximization, load minimization and design of wind farm layout. Local flow information at each wind turbine location can be obtained by using the response of the wind turbines, which are consequently used as distributed sensors. This paper proposes the use of hub loads to track the position of wakes within a wind farm. Simulation experiments conducted within a high-fidelity aeroservoelastic environment demonstrate the performance of the new method.

  19. Collective versus hub activation of epidemic phases on networks

    CERN Document Server

    Ferreira, Silvio C; Pastor-Satorras, Romualdo

    2015-01-01

    We consider a general criterion to discern the nature of the threshold in epidemic models on scale-free (SF) networks. Comparing the epidemic lifespan of the nodes with largest degrees with the infection time between them, we propose a general dual scenario, in which the epidemic transition is either ruled by a hub activation process, leading to a null threshold in the thermodynamic limit, or given by a collective activation process, corresponding to a standard phase transition with a finite threshold. We validate the proposed criterion applying it different to epidemic models, with waning immunity or heterogeneous infection rates.

  20. Colossal Seebeck effect enhanced by quasi-ballistic phonons dragging massive electrons in FeSb2

    Science.gov (United States)

    Takahashi, H.; Okazaki, R.; Ishiwata, S.; Taniguchi, H.; Okutani, A.; Hagiwara, M.; Terasaki, I.

    2016-09-01

    Phonon transport is an essential property of thermoelectric materials. Although the phonon carries heat, which reduces the thermoelectric efficiency, it contributes positively to the Seebeck coefficient S through the phonon-drag effect, as typified by the high-purity semiconductors, which show fairly large S at cryogenic temperatures. Although such a large S is attractive in terms of Peltier cooling, a clear guiding principle for designing thermoelectric materials enriched by the phonon-drag effect remains to be established. Here we demonstrate that a correlated semiconductor, FeSb2, is a promising thermoelectric material featuring quasi-ballistic phonons dragging d electrons with large effective mass. By changing the sample size within the sub-millimetre order for high-purity single crystals, we succeed in substantially increasing S to as much as -27 mV K-1 at low temperatures. Our results exemplify a strategy for exploring phonon-drag-based thermoelectric materials, the performance of which can be maximized by combining heavy electrons with ballistic phonons.

  1. Colossal Seebeck effect enhanced by quasi-ballistic phonons dragging massive electrons in FeSb2.

    Science.gov (United States)

    Takahashi, H; Okazaki, R; Ishiwata, S; Taniguchi, H; Okutani, A; Hagiwara, M; Terasaki, I

    2016-09-06

    Phonon transport is an essential property of thermoelectric materials. Although the phonon carries heat, which reduces the thermoelectric efficiency, it contributes positively to the Seebeck coefficient S through the phonon-drag effect, as typified by the high-purity semiconductors, which show fairly large S at cryogenic temperatures. Although such a large S is attractive in terms of Peltier cooling, a clear guiding principle for designing thermoelectric materials enriched by the phonon-drag effect remains to be established. Here we demonstrate that a correlated semiconductor, FeSb2, is a promising thermoelectric material featuring quasi-ballistic phonons dragging d electrons with large effective mass. By changing the sample size within the sub-millimetre order for high-purity single crystals, we succeed in substantially increasing S to as much as -27 mV K(-1) at low temperatures. Our results exemplify a strategy for exploring phonon-drag-based thermoelectric materials, the performance of which can be maximized by combining heavy electrons with ballistic phonons.

  2. Fair Exchange in Strand Spaces

    Directory of Open Access Journals (Sweden)

    Joshua D. Guttman

    2009-10-01

    Full Text Available Many cryptographic protocols are intended to coordinate state changes among principals. Exchange protocols coordinate delivery of new values to the participants, e.g. additions to the set of values they possess. An exchange protocol is fair if it ensures that delivery of new values is balanced: If one participant obtains a new possession via the protocol, then all other participants will, too. Fair exchange requires progress assumptions, unlike some other protocol properties. The strand space model is a framework for design and verification of cryptographic protocols. A strand is a local behavior of a single principal in a single session of a protocol. A bundle is a partially ordered global execution built from protocol strands and adversary activities. The strand space model needs two additions for fair exchange protocols. First, we regard the state as a multiset of facts, and we allow strands to cause changes in this state via multiset rewriting. Second, progress assumptions stipulate that some channels are resilient-and guaranteed to deliver messages-and some principals are assumed not to stop at certain critical steps. This method leads to proofs of correctness that cleanly separate protocol properties, such as authentication and confidentiality, from invariants governing state evolution. G. Wang's recent fair exchange protocol illustrates the approach.

  3. Toddlers Selectively Help Fair Agents

    Directory of Open Access Journals (Sweden)

    Luca Surian

    2017-06-01

    Full Text Available Previous research showed that infants and toddlers are inclined to help prosocial agents and assign a positive valence to fair distributions. Also, they expect that positive and negative actions directed toward distributors will conform to reciprocity principles. This study investigates whether toddlers are selective in helping others, as a function of others’ previous distributive actions. Toddlers were presented with real-life events in which two actresses distributed resources either equally or unequally between two puppets. Then, they played together with a ball that accidentally fell to the ground and asked participants to help them to retrieve it. Participants preferred to help the actress who performed equal distributions. This finding suggests that by the second year children’s prosocial actions are modulated by their emerging sense of fairness.HighlightsToddlers (mean age = 25 months are selective in helping distributors.Toddlers prefer helping a fair rather than an unfair distributor.Toddlers’ selective helping provides evidence for an early sense of fairness.

  4. Evolutionary dynamics of group fairness.

    Science.gov (United States)

    Santos, Fernando P; Santos, Francisco C; Paiva, Ana; Pacheco, Jorge M

    2015-08-07

    The emergence and impact of fairness is commonly studied in the context of 2-person games, notably the Ultimatum Game. Often, however, humans face problems of collective action involving more than two individuals where fairness is known to play a very important role, and whose dynamics cannot be inferred from what is known from 2-person games. Here, we propose a generalization of the Ultimatum Game for an arbitrary number of players--the Multiplayer Ultimatum Game. Proposals are made to a group of responders who must individually reject or accept the proposal. If the total number of individual acceptances stands below a given threshold, the offer will be rejected; otherwise, the offer will be accepted, and equally shared by all responders. We investigate the evolution of fairness in populations of individuals by means of evolutionary game theory, providing both analytical insights and results from numerical simulations. We show how imposing stringent consensuses significantly increases the value of the proposals, leading to fairer outcomes and more tolerant players. Furthermore, we show how stochastic effects--such as imitation errors and/or errors when assessing the fitness of others--may further enhance the overall success in reaching fair collective action. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Ongoing Issues in Test Fairness

    Science.gov (United States)

    Camilli, Gregory

    2013-01-01

    In the attempt to identify or prevent unfair tests, both quantitative analyses and logical evaluation are often used. For the most part, fairness evaluation is a pragmatic attempt at determining whether procedural or substantive due process has been accorded to either a group of test takers or an individual. In both the individual and comparative…

  6. Science Fair Projects: The Environment.

    Science.gov (United States)

    Bonnet, Bob; Keen, Dan

    This book approaches the development of science fair projects from the point of view that science should be enjoyable, interesting, and thought-provoking. The scientific concepts introduced here will later help young students to understand more advanced scientific principles. These projects develop skills such as classification, making measured…

  7. A Kinder-Science Fair

    Science.gov (United States)

    Torres, Angelica; Vitti, Debbye

    2007-01-01

    A science fair might be the last thing you think of when planning a kindergarten science curriculum, but the authors found it to be the perfect avenue for teaching their students science-process skills. Here they share their steps in teaching science-process skills and assembling student projects in a kindergarten classroom throughout the year.…

  8. Fair Finance: gaat dat samen?

    NARCIS (Netherlands)

    Boersma, Margreet

    2014-01-01

    Op 13 februari jl. organiseerden studievereniging HSE Faktor, het Instituut FEM en Oikocredit (een bedrijf dat microkredieten verstrekt aan arme mensen in ontwikkelingslanden) het Fair Finance Symposium. Margreet Boersma gaf een lezing over haar kijk op een betere (financiële) wereld, mede gericht o

  9. Atoms at the Science Fair

    Energy Technology Data Exchange (ETDEWEB)

    LeCompte, Robert G. [AEC Division of Technical Information; Wood, Burrell L. [AEC Division of Special Projects

    1968-01-01

    The United States Atomic Energy Commission has prepared this booklet to help young science fair exhibitors, their science teachers, project counselors, and parents. The booklet suggests some of the numerous nuclear topics on which students can base meaningful science projects. It offers all exhibitors advice on how to plan, design, and construct successful exhibits.

  10. Children's Concepts of Fair Sharing.

    Science.gov (United States)

    Huntsman, Robert W.

    1984-01-01

    The Damon hierarchy of development of children's sense of positive justice is examined for its usefulness in predicting fairness in behavior and reliability in age patterning of its stated levels of reasoning. The hierarchy's value as a developmental schedule for teacher guidance may be questionable. (Author)

  11. The hubs of the human connectome are generally implicated in the anatomy of brain disorders.

    Science.gov (United States)

    Crossley, Nicolas A; Mechelli, Andrea; Scott, Jessica; Carletti, Francesco; Fox, Peter T; McGuire, Philip; Bullmore, Edward T

    2014-08-01

    Brain networks or 'connectomes' include a minority of highly connected hub nodes that are functionally valuable, because their topological centrality supports integrative processing and adaptive behaviours. Recent studies also suggest that hubs have higher metabolic demands and longer-distance connections than other brain regions, and therefore could be considered biologically costly. Assuming that hubs thus normally combine both high topological value and high biological cost, we predicted that pathological brain lesions would be concentrated in hub regions. To test this general hypothesis, we first identified the hubs of brain anatomical networks estimated from diffusion tensor imaging data on healthy volunteers (n = 56), and showed that computational attacks targeted on hubs disproportionally degraded the efficiency of brain networks compared to random attacks. We then prepared grey matter lesion maps, based on meta-analyses of published magnetic resonance imaging data on more than 20 000 subjects and 26 different brain disorders. Magnetic resonance imaging lesions that were common across all brain disorders were more likely to be located in hubs of the normal brain connectome (P brain disorders had lesions that were significantly more likely to be located in hubs (P human brain networks are more likely to be anatomically abnormal than non-hubs in many (if not all) brain disorders. © The Author (2014). Published by Oxford University Press on behalf of the Guarantors of Brain.

  12. Design of targeted libraries against the human Chk1 kinase using PGVL Hub.

    Science.gov (United States)

    Peng, Zhengwei; Hu, Qiyue

    2011-01-01

    PGVL Hub is a Pfizer internal desktop tool for chemical library and singleton design. In this chapter, we give a short introduction to PGVL Hub, the core workflow it supports, and the rich design capabilities it provides. By re-creating two legacy targeted libraries against the human checkpoint kinase 1 (Chk1) as a showcase, we illustrate how PGVL Hub could be used to help library designers carry out the steps in library design and realize design objectives such as SAR expansion and improvement in both kinase selectivity and compound aqueous solubility. Finally we share several tips about library design and usage of PGVL Hub.

  13. Afterbody Drag. Volume 3. Literature Survey.

    Science.gov (United States)

    1980-06-01

    34 AGARD, Otta- wa, June 1955. 34. Faru, I., "Experimental Determination of Base Pressures at Supersonic Velocities." Bumblebee Report 106, Johns ...Taylor Model Basin Aero Report 857, January 1954. 68. Pietrangeli, G.J., "The Determination of Afterbody Drag at Transonic Speeds." Johns Hopkins...34 NASATND-7095, 1972. Coltrane , L.C., "Investigation of Two Bluff Shapes in Axial Free Flight Over a Mach Number Range from 0.35 to 2.15." NACARM L58A16

  14. Coulombic dragging of molecular assemblies on nanotubes

    Science.gov (United States)

    Kral, Petr; Sint, Kyaw; Wang, Boyang

    2009-03-01

    We show by molecular dynamics simulations that polar molecules, ions and their assemblies could be Coulombically dragged on the surfaces of single-wall carbon and boron-nitride nanotubes by ionic solutions or individual ions moving inside the nanotubes [1,2]. We also briefly discuss highly selective ionic sieves based on graphene monolayers with nanopores [3]. These phenomena could be applied in molecular delivery, separation and desalination.[3pt] [1] Boyang Wang and Petr Kral, JACS 128, 15984 (2006). [0pt] [2] Boyang Wang and Petr Kral, Phys. Rev. Lett. 101, 046103 (2008). [0pt] [3] Kyaw Sint, Boyang Wang and Petr Kral, JACS, ASAP (2008).

  15. Gravitational Capture of Asteroids by Gas Drag

    Directory of Open Access Journals (Sweden)

    E. Vieira Neto

    2009-01-01

    captured by the planet got its velocity reduced and could been trapped as an irregular satellite. It is well known that, depending on the time scale of the gas envelope, an asteroid will spiral and collide with the planet. So, we simulate the passage of the asteroid in the gas envelope with its density decreasing along the time. Using this approach, we found effective captures, and have a better understanding of the whole process. Finally, we conclude that the origin of the irregular satellites cannot be attributed to the gas drag capture mechanism alone.

  16. Drag phenomena from holographic massive gravity

    Science.gov (United States)

    Baggioli, Matteo; Brattan, Daniel K.

    2017-01-01

    We consider the motion of point particles in a strongly coupled field theory with broken translation invariance. We obtain the energy and momentum loss rates and drag coefficients for a class of such particles by solving for the motion of classical strings in holographic massive gravity. At low temperatures compared to the graviton mass the behaviour of the string is controlled by the appearance of an exotic ground state with non-zero entropy at zero temperature. Additionally, we find an upper bound on the diffusion constant for a collection of these particles which is saturated when the mass of the graviton goes to zero.

  17. Drag phenomena from holographic massive gravity

    CERN Document Server

    Baggioli, Matteo

    2015-01-01

    We consider the motion of point particles in a strongly coupled field theory with broken translation invariance. We obtain the energy and momentum loss rates and drag coefficients for a class of such particles by solving for the motion of classical strings in holographic massive gravity. At low temperatures compared to the graviton mass the behaviour of the string is controlled by the appearance of an exotic ground state with non-zero entropy at zero temperature. Additionally we find an upper bound on the diffusion constant for a collection of these particles which is saturated when the mass of the graviton goes to zero.

  18. On Nature of Plasmonic Drag Effect

    CERN Document Server

    Durach, Maxim

    2016-01-01

    Light-matter momentum transfer in plasmonic materials is theoretically discussed in context of the modified plasmonic pressure mechanism, taking into account electron thermalization process. We show that our approach explains the observed in experiments relationship between the photoinduced electromotive force and absorption, emphasizes the quantum nature of plasmon-electron interaction, and allows one to correctly calculate the magnitude of the plasmon drag emf in flat metal films for the first time. We extend our theory on the films with modulated profiles and show that simple relationship between plasmonic energy and momentum transfer holds for the case of laminar electron drift and relatively small amplitudes of height modulation.

  19. Evaluation of nacelle drag using Computational Fluid Dynamics

    Directory of Open Access Journals (Sweden)

    Luis Gustavo Trapp

    2010-08-01

    Full Text Available Thrust and drag components must be defined and properly accounted in order to estimate aircraft performance, and this hard task is particularty essential for propulsion system where drag components are functions of engine operating conditions. The present work describes a numerical method used to calculate the drag in different nacelles, long and short ducted. Two- and three-dimensional calculations were performed, solving the Reynolds Averaged Navier-Stokes (RANS equations with a commercial Computational Fluid Dynamics (CFD code. It is then possible to obtain four drag components: wave, induced, viscous and spurious drag using a far-field formulation. An expression in terms of entropy variations was shown and drag for different nacelle geometries was estimated.

  20. PASSENGER SERVICE QUALITY PARAMETERS ASSESSMENT AT TRANSPORT INTERCHANGE HUBS

    Directory of Open Access Journals (Sweden)

    Kozlov Pavel Igorevich

    2017-05-01

    Full Text Available The article discusses a quality assessment method for transport decisions made in transport interchange hubs. Analysis of domestic regulatory documentation and international experience on this subject is performed. It is stated that the domestic regulatory documentation lacks such method of assessment. Special attention is paid to study of pedestrian flows in interchange complexes of intermodal transport interchange hubs. The aim of the study is development of the Level of Service comprehensive assessment criterion by analogy with the international practice. The authors propose to use the queueing theory with elements of the theory of graphs, techniques and regularities that underlie the Level of Service (service factor applied in planning and location of TIH in the USA as well as data from field surveys carried out by the pedestrian flows video detection method. During the field surveys it is planned to perform analysis of external and internal factors influencing the formation and composition of a pedestrian flow, to determine quantitative values of the main parameters of pedestrian flow (density, speed, intensity and regularities of their variation depending on the design features of pedestrian traffic environment. Determination of passenger service quality factors in TIH will help to develop an integral criterion based on the Level of Service, taking into account the specifics of TIH functioning in Russia as well as a methodology that allows a reasonable choice of combinations of structural elements and planning parameters of pedestrian traffic objects which will let to reduce construction costs and operating costs for location of interchange complexes.

  1. Disinfection of Needleless Connector Hubs: Clinical Evidence Systematic Review

    Science.gov (United States)

    Moureau, Nancy L.

    2015-01-01

    Background. Needleless connectors (NC) are used on virtually all intravascular devices, providing an easy access point for infusion connection. Colonization of NC is considered the cause of 50% of postinsertion catheter-related infections. Breaks in aseptic technique, from failure to disinfect, result in contamination and subsequent biofilm formation within NC and catheters increasing the potential for infection of central and peripheral catheters. Methods. This systematic review evaluated 140 studies and 34 abstracts on NC disinfection practices, the impact of hub contamination on infection, and measures of education and compliance. Results. The greatest risk for contamination of the catheter after insertion is the NC with 33–45% contaminated, and compliance with disinfection as low as 10%. The optimal technique or disinfection time has not been identified, although scrubbing with 70% alcohol for 5–60 seconds is recommended. Studies have reported statistically significant results in infection reduction when passive alcohol disinfection caps are used (48–86% reduction). Clinical Implications. It is critical for healthcare facilities and clinicians to take responsibility for compliance with basic principles of asepsis compliance, to involve frontline staff in strategies, to facilitate education that promotes understanding of the consequences of failure, and to comply with the standard of care for hub disinfection. PMID:26075093

  2. Disinfection of Needleless Connector Hubs: Clinical Evidence Systematic Review

    Directory of Open Access Journals (Sweden)

    Nancy L. Moureau

    2015-01-01

    Full Text Available Background. Needleless connectors (NC are used on virtually all intravascular devices, providing an easy access point for infusion connection. Colonization of NC is considered the cause of 50% of postinsertion catheter-related infections. Breaks in aseptic technique, from failure to disinfect, result in contamination and subsequent biofilm formation within NC and catheters increasing the potential for infection of central and peripheral catheters. Methods. This systematic review evaluated 140 studies and 34 abstracts on NC disinfection practices, the impact of hub contamination on infection, and measures of education and compliance. Results. The greatest risk for contamination of the catheter after insertion is the NC with 33–45% contaminated, and compliance with disinfection as low as 10%. The optimal technique or disinfection time has not been identified, although scrubbing with 70% alcohol for 5–60 seconds is recommended. Studies have reported statistically significant results in infection reduction when passive alcohol disinfection caps are used (48–86% reduction. Clinical Implications. It is critical for healthcare facilities and clinicians to take responsibility for compliance with basic principles of asepsis compliance, to involve frontline staff in strategies, to facilitate education that promotes understanding of the consequences of failure, and to comply with the standard of care for hub disinfection.

  3. Design and Development of an Integrated Workstation Automation Hub

    Energy Technology Data Exchange (ETDEWEB)

    Weber, Andrew; Ghatikar, Girish; Sartor, Dale; Lanzisera, Steven

    2015-03-30

    Miscellaneous Electronic Loads (MELs) account for one third of all electricity consumption in U.S. commercial buildings, and are drivers for a significant energy use in India. Many of the MEL-specific plug-load devices are concentrated at workstations in offices. The use of intelligence, and integrated controls and communications at the workstation for an Office Automation Hub – offers the opportunity to improve both energy efficiency and occupant comfort, along with services for Smart Grid operations. Software and hardware solutions are available from a wide array of vendors for the different components, but an integrated system with interoperable communications is yet to be developed and deployed. In this study, we propose system- and component-level specifications for the Office Automation Hub, their functions, and a prioritized list for the design of a proof-of-concept system. Leveraging the strength of both the U.S. and India technology sectors, this specification serves as a guide for researchers and industry in both countries to support the development, testing, and evaluation of a prototype product. Further evaluation of such integrated technologies for performance and cost is necessary to identify the potential to reduce energy consumptions in MELs and to improve occupant comfort.

  4. Rotating systems, universal features in dragging and anti-dragging effects, and bounds onto angular momentum

    CERN Document Server

    Karkowski, Janusz; Malec, Edward; Pirog, Michal; Xie, Naqing

    2016-01-01

    We consider stationary, axially symmetric toroids rotating around spinless black holes, assuming the general-relativistic Keplerian rotation law, in the first post-Newtonian approximation. Numerical investigation shows that the angular momentum accumulates almost exclusively within toroids. It appears that various types of dragging (anti-dragging) effects are positively correlated with the ratio $M_\\mathrm{D}/m$ ($M_\\mathrm{D}$ is the mass of a toroid and $m$ is the mass of the black hole) - moreover, their maxima are proportional to $M_\\mathrm{D}/m$. The horizontal sizes of investigated toroids range from c. 50 to c. 450 of Schwarzschild radii $R_\\mathrm{S}$ of the central black hole; their mass $M_\\mathrm{D} \\in (10^{-4}m, 40m)$ and the radial size of the system is c. 500 $R_\\mathrm{S}$. We found that the relative strength of various dragging (anti-dragging) effects does not change with the mass ratio, but it depends on the size of toroids. Several isoperimetric inequalities involving angular momentum are s...

  5. Drag prediction method of powered-on civil aircraft based on thrust drag bookkeeping

    Directory of Open Access Journals (Sweden)

    Zhang Yufei

    2015-08-01

    Full Text Available A drag prediction method based on thrust drag bookkeeping (TDB is introduced for civil jet propulsion/airframe integration performance analysis. The method is derived from the control volume theory of a powered-on nacelle. Key problem of the TDB is identified to be accurate prediction of velocity coefficient of the powered-on nacelle. Accuracy of CFD solver is validated by test cases of the first AIAA Propulsion Aerodynamics Workshop. Then the TDB method is applied to thrust and drag decomposing of a realistic aircraft. A linear relation between the computations assumed free stream Mach number and the velocity coefficient result is revealed. The thrust losses caused by nozzle internal drag and pylon scrubbing are obtained by the isolated nacelle and mapped on to the in-flight whole configuration analysis. Effects of the powered-on condition are investigated by comparing through-flow configuration with powered-on configuration. The variance on aerodynamic coefficients and pressure distribution is numerically studied.

  6. An Analytical Method for Positioning Drag Anchors in Seabed Soils

    Institute of Scientific and Technical Information of China (English)

    张炜; 刘海笑; 李新仲; 李清平; 曹静

    2015-01-01

    Positioning drag anchors in seabed soils are strongly influenced not only by the properties of the anchor and soil, but also by the characteristics of the installation line. The investigation on the previous prediction methods related to anchor positioning demonstrates that the prediction of the anchor position during dragging has inevitably introduced some key and unsubstantiated hypotheses and the applicability of these methods is limited. In the present study, the interactional system between the drag anchor and installation line is firstly introduced for the analysis of anchor positioning. Based on the two mechanical models for embedded lines and drag anchors, the positioning equations for drag anchors have been derived both for cohesive and noncohesive soils. Since the drag angle at the shackle is the most important parameter in the positioning equations, a novel analytical method that can predict both the variation and the exact value of the drag angle at the shackle is proposed. The analytical method for positioning drag anchors which combines the interactional system between the drag anchor and the installation line has provided a reasonable theoretic approach to investigate the anchor behaviors in soils. By comparing with the model flume experiments, the sensitivity, effectiveness and veracity of the positioning method are well verified.

  7. Correlated Coulomb drag in capacitively coupled quantum-dot structures

    DEFF Research Database (Denmark)

    Kaasbjerg, Kristen; Jauho, Antti-Pekka

    2016-01-01

    We study theoretically Coulomb drag in capacitively coupled quantum dots (CQDs) -- a biasdriven dot coupled to an unbiased dot where transport is due to Coulomb mediated energy transfer drag. To this end, we introduce a master-equation approach which accounts for higher-order tunneling (cotunneling....... Interestingly, the direction of the drag current is not determined by the drive current, but by an interplay between the energy-dependent lead couplings. Studying the drag mechanism in a graphene-based CQD heterostructure, we show that the predictions of our theory are consistent with recent experiments...

  8. Bionic Research on Bird Feather for Drag Reduction

    Directory of Open Access Journals (Sweden)

    Beibei Feng

    2015-02-01

    Full Text Available To reduce friction drag with bionic method in a more feasible way, the surface microstructure of bird feather was analyzed attempting to reveal the biologic features responding to skin friction drag reduction. Then comparative bionic surface mimicking bird feather was fabricated through hot-rolling technology for drag reduction. The microriblet film was formed on a PVC substrate through a self-developed hot-rolling equipment. The bionic surface with micron-scale riblets formed spontaneously due to the elastic-plastic deformation of PVC in high temperature and high pressure environment. Comparative experiments between micro-structured bionic surface and smooth surface were performed in a wind tunnel to evaluate the effect of bionic surface on drag reduction, and significant drag reduction efficiency was obtained. Numerical simulation results show that microvortex induced in the solid-gas interface of bionic surface has the effect of shear stress reduction and the small level of an additional pressure drag resulting from pressure distribution deviation on bird feather like surface, hence reducing the skin friction drag significantly. Therefore, with remarkable drag reduction performance and simple fabrication technology, the proposed drag reduction technique shows the promise for practical applications.

  9. Drag reduction properties of superhydrophobic mesh pipes

    Science.gov (United States)

    Geraldi, Nicasio R.; Dodd, Linzi E.; Xu, Ben B.; Wells, Gary G.; Wood, David; Newton, Michael I.; McHale, Glen

    2017-09-01

    Even with the recent extensive study into superhydrophobic surfaces, the fabrication of such surfaces on the inside walls of a pipe remains challenging. In this work we report a convenient bi-layered pipe design using a thin superhydrophobic metallic mesh formed into a tube, supported inside another pipe. A flow system was constructed to test the fabricated bi-layer pipeline, which allowed for different constant flow rates of water to be passed through the pipe, whilst the differential pressure was measured, from which the drag coefficient (ƒ) and Reynolds numbers (Re) were calculated. Expected values of ƒ were found for smooth glass pipes for the Reynolds number (Re) range 750-10 000, in both the laminar and part of the turbulent regimes. Flow through plain meshes without the superhydrophobic coating were also measured over a similar range (750  superhydrophobic coating, ƒ was found for 4000  superhydrophobic mesh can support a plastron and provide a drag reduction compared to a plain mesh, however, the plastron is progressively destroyed with use and in particular at higher flow rates.

  10. The drag force during the transient regime

    CERN Document Server

    Souza, P V S; de Oliveira, P M C

    2015-01-01

    In this paper, we analyze the drag force acting on a cylinder in a wind tunnel. The inspiration comes from an experimental result: a small, light ball falls on air; its speed increases, reaches a maximum, decreases and finally stabilizes. This surprising breaking behavior is due to the gradual formation of the so-called von K\\'arm\\'an street of air vortices behind the ball: while it is not completely formed, the transient drag force is smaller than the known steady state value and the ball can reach speeds higher than its final value. To show it, we treat the similar problem of a cylinder inside a wind tunnel suddenly switched on, by solving the Navier-Stokes dynamic equation. We use a finite difference method with successive relaxations on a grid. We also treat the case of a rotating cylinder, leading to the Magnus force. The novelty is the method we use to calculate these forces, which avoids the traditional surface integration of velocity gradients; the latter demands a very precise determination of the ve...

  11. Drag Force Anemometer Used in Supersonic Flow

    Science.gov (United States)

    Fralick, Gustave C.

    1998-01-01

    To measure the drag on a flat cantilever beam exposed transversely to a flow field, the drag force anemometer (beam probe) uses strain gauges attached on opposite sides of the base of the beam. This is in contrast to the hot wire anemometer, which depends for its operation on the variation of the convective heat transfer coefficient with velocity. The beam probe retains the high-frequency response (up to 100 kHz) of the hot wire anemometer, but it is more rugged, uses simpler electronics, is relatively easy to calibrate, is inherently temperature compensated, and can be used in supersonic flow. The output of the probe is proportional to the velocity head of the flow, 1/2 rho u(exp 2) (where rho is the fluid density and u is the fluid velocity). By adding a static pressure tap and a thermocouple to measure total temperature, one can determine the Mach number, static temperature, density, and velocity of the flow.

  12. THE (UN?) FAIRNESS OF FAIR VALUE: SFAS 157, IRVING FISHER AND GECON

    National Research Council Canada - National Science Library

    Paulo Roberto Barbosa Lustosa

    2017-01-01

    ... – Fair Value Measurements to traditional economic-accounting concepts. Background: The expansion of situations in which fair value measurement is required makes more difficult to ensure that the computed measure of value is actually fair...

  13. FAIR

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    HI,大腕儿!12月15日晚,一个由上千光点组成的巨大奥迪Logo悬挂在北京国贸中心展厅外墙,展厅内“百年奥迪”中国庆典也已成为回顾百年奥迪辉煌历史、展示品牌领先科技的舞台。

  14. CERN Scientific Book Fair 2008

    CERN Document Server

    DSU Unit

    2008-01-01

    The CERN Bookshop and CERN Library invite you to attend the 2008 CERN Book Fair 2008, a three-day scientific book festival offering you the opportunity to meet key publishers and electronic book suppliers and to browse and purchase books at significant discounts. Some ten companies will be participating and will bring with them a selection of titles in physics, technology, mathematics, engineering and popular science. There will also be a number of tie-in events intended to give you an insight into the writing and publishing process from authors within our own community. Come along and meet the authors, discuss your book ideas with the publishers’ representatives or simply browse the books on offer. The Fair will take place in Building 500 in the area near the Main Auditorium, and special presentations (as detailed below) will be held in rooms nearby or in the Library. Participating publishers and book traders include: Cambridge ...

  15. The NUSTAR program at FAIR

    Directory of Open Access Journals (Sweden)

    Herlert Alexander

    2014-04-01

    Full Text Available The NUSTAR Collaboration brings together several hundred scientists to form one of the four scientific pillars of the future FAIR facility. NUSTAR aims at the exploitation of intense radioactive beams with energies up to 1.5 GeV/u in order to explore nuclei with large neutron or proton excess. The project has evolved over the last years and now reached a state where a large fraction of the core program is financed, partly built, and even ready for operation. With the signing of the FAIR convention in 2010 and the start of construction, the sub-projects in NUSTAR gain momentum and look forward to commissioning and first beams in this decade. The present status of the project will be presented, focusing on the instrumentation to be applied in the various experimental areas behind the Super-FRS fragment separator, which is the central instrument of NUSTAR.

  16. HOW APPRAISERS DEVELOP FAIR VALUE

    Directory of Open Access Journals (Sweden)

    MIROSLAV ŠKODA

    2012-01-01

    Full Text Available Management is responsible for its own financial decisions. If we take into account, that fair value concept was shown in financial crisis as something that does not work anymore in this way; there is a big need to develop it for the future. Non-professional readers of financial statements believe, however, that company financials are the work of the public accounting firm that had signed the audit certificate. The main reason for bringing this point up is that when companies disclose Fair Value (FV information in their financial statements, they are taking responsibility for the values disclosed. Management may often be encouraged to utilize the services of an outside professional, but at the end of the day, the outside appraiser is a hired gun. Although the appraiser has to take responsibility for his own work, hiring the appraiser does not absolve management of its ultimate responsibility. The obverse of this is also true. Management does not have to hire the appraiser to develop any fair value disclosures made in the financial statements. Developing FV information is not recommended as a do-it yourself undertaking, there is nothing in Generally Accepted Accounting Principles (GAAP or Securities Exchange Commission (SEC regulations, however, that requires an outside appraiser.

  17. Knowledge Hub y los recursos educativos abiertos en Contaduría

    OpenAIRE

    Farías Martínez, Gabriela María

    2010-01-01

    Desafíos de la educación superior en México; Formación académica y profesional en contaduría; Knowledge Hub como medio para compartir y construir conocimiento; Iniciativa Knowledge Hub IES Contaduría

  18. 14 CFR 158.30 - PFC Authorization at Non-Hub Airports.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false PFC Authorization at Non-Hub Airports. 158... (CONTINUED) AIRPORTS PASSENGER FACILITY CHARGES (PFC'S) Application and Approval § 158.30 PFC Authorization at Non-Hub Airports. (a) General. This section specifies the procedures a public agency controlling...

  19. The Complexities and Challenges of Regional Education Hubs: Focus on Malaysia

    Science.gov (United States)

    Knight, Jane; Morshidi, Sirat

    2011-01-01

    The race to establish regional education hubs is a recent development in cross-border higher education. This article briefly examines the rationales and strategies used by three countries in the Middle East and three in South East Asia which are working towards positioning themselves as regional education hubs. The different approaches and…

  20. Knowledge Hub y los recursos educativos abiertos en Contaduría

    OpenAIRE

    Farías Martínez, Gabriela María

    2013-01-01

    Desafíos de la educación superior en México; Formación académica y profesional en contaduría; Knowledge Hub como medio para compartir y construir conocimiento; Iniciativa Knowledge Hub IES Contaduría

  1. A multi-objective imperialist competitive algorithm for a capacitated hub covering location problem

    Directory of Open Access Journals (Sweden)

    M. Mohammadi

    2011-01-01

    Full Text Available The hub location problem appears in a variety of applications, including airline systems, cargo delivery systems and telecommunication network design. Hub location problems deal with finding the location of hub facilities and the allocation of demand nodes to these located hub facilities. In this paper, a new model for the capacitated single allocation hub covering location problem is presented. Instead of using capacity constraints to limit the amount of flow received by the hubs, the second objective function is introduced to minimize service times in the hubs. The service time in the hubs includes the waiting time of received flows in a queue and the time to get services. Due to the NP-hardness of the problem, a new weight-based multi-objective imperialist competitive algorithm (MOICA is designed to find near-optimal solutions. To validate the performance of the proposed algorithm, the solutions obtained by the MOICA are compared by the exact solutions of the mathematical programming model.

  2. Domestic Output of Aluminium Alloy Hub Surpassing 70 million in 2007

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    <正>According to a report from the hub branch of China Association of Automobile Manufactur- ers,China has produced a total of more than 70 million aluminium alloy hubs in 2007,a year- on-year growth over 25%,while consuming over 700,000 tons of primary aluminium the whole year.

  3. Optimal Scheduling of a Multi-Carrier Energy Hub Supplemented By Battery Energy Storage Systems

    DEFF Research Database (Denmark)

    Javadi, Mohammad Sadegh; Anvari-Moghaddam, Amjad; Guerrero, Josep M.

    2017-01-01

    This paper introduces a management model for optimal scheduling of a multi-carrier energy hub. In the proposed hub, three types of assets are considered: dispersed generating systems (DGs) such as micro-combined heat and power (mCHP) units, storage devices such as battery-based electrical storage...

  4. Network performance, hub connectivity potential, and competitive position of primary airports in Asia/Pacific region

    NARCIS (Netherlands)

    Matsumoto, H.; Veldhuis, J.; de Wit, J.; Burghouwt, G.

    2008-01-01

    Recently, hub-and-spoke network configurations are more and more developed in the Asia/Pacific region. In this paper, it is argued that the measurement of network performance in hub-and-spoke systems should take into account the quantity and quality of both direct and indirect connections. The NetSc

  5. The Complexities and Challenges of Regional Education Hubs: Focus on Malaysia

    Science.gov (United States)

    Knight, Jane; Morshidi, Sirat

    2011-01-01

    The race to establish regional education hubs is a recent development in cross-border higher education. This article briefly examines the rationales and strategies used by three countries in the Middle East and three in South East Asia which are working towards positioning themselves as regional education hubs. The different approaches and…

  6. Competition and coordination in the U.S. airline hub-to-hub markets: An industry pre-merger case study

    Directory of Open Access Journals (Sweden)

    Prasun Bhattacharjee

    2016-04-01

    Full Text Available Purpose: This paper investigates the nature of conduct that existed in the U.S. airline hub-to-hub markets prior to the recent merger wave of the legacy carriers. We explore the strategic importance of network carrier hubs in form of “spheres of influence” on airline market conduct. We also simultaneously recognize the overgrowing role played by Low Cost Carriers (LCC over the years by estimating two conduct parameters - one in markets where LCCs directly compete head-to-head with legacy carriers and the other for markets which LCCs do not serve but has presence in the hub airports or adjacent airports comprising the market endpoints. Thus our supply side framework also sheds some light on the issue of perfect contestability in airline industry. Design/methodology/approach: We estimate a structural oligopoly model for differentiated products with competitive interactions using DB1B data for first quarter of 2004. Findings: Our results imply that the nature of competition is more aggressive relative to Bertrand behavior in hub-to-hub markets and that these markets are less than perfectly contestable. Originality/value: This paper adds to the empirical literature of airline competition by enabling estimation of the actual conduct parameter assuming firm price setting behavior in presence of product differentiation. Contrary to existing literature on airline competition, a structural model enables us to systematically separate out effects of demand, cost and strategic factors on observed airline prices.

  7. Sports Fair Play and Critical Perspective

    Institute of Scientific and Technical Information of China (English)

    许晓峰

    2014-01-01

    Here, this paper suggests that CIFP tamp the ideal of fair play, re-establish the fair play value system, and conduct effective reform of organization and cause correspondingly instead of becoming agent of European centralism and American hegemonism.

  8. Constructing invariant fairness measures for surfaces

    DEFF Research Database (Denmark)

    Gravesen, Jens; Ungstrup, Michael

    2002-01-01

    The paper proposes a rational method to derive fairness measures for surfaces. It works in cases where isophotes, reflection lines, planar intersection curves, or other curves are used to judge the fairness of the surface. The surface fairness measure is derived by demanding that all the given...... curves should be fair with respect to an appropriate curve fairness measure. The method is applied to the field of ship hull design where the curves are plane intersections. The method is extended to the case where one considers, not the fairness of one curve, but the fairness of a one parameter family...... of curves. Six basic third order invariants by which the fairing measures can be expressed are defined. Furthermore, the geometry of a plane intersection curve is studied, and the variation of the total, the normal, and the geodesic curvature and the geodesic torsion is determined....

  9. Features analysis for identification of date and party hubs in protein interaction network of Saccharomyces Cerevisiae

    Directory of Open Access Journals (Sweden)

    Araabi Babak N

    2010-12-01

    Full Text Available Abstract Background It has been understood that biological networks have modular organizations which are the sources of their observed complexity. Analysis of networks and motifs has shown that two types of hubs, party hubs and date hubs, are responsible for this complexity. Party hubs are local coordinators because of their high co-expressions with their partners, whereas date hubs display low co-expressions and are assumed as global connectors. However there is no mutual agreement on these concepts in related literature with different studies reporting their results on different data sets. We investigated whether there is a relation between the biological features of Saccharomyces Cerevisiae's proteins and their roles as non-hubs, intermediately connected, party hubs, and date hubs. We propose a classifier that separates these four classes. Results We extracted different biological characteristics including amino acid sequences, domain contents, repeated domains, functional categories, biological processes, cellular compartments, disordered regions, and position specific scoring matrix from various sources. Several classifiers are examined and the best feature-sets based on average correct classification rate and correlation coefficients of the results are selected. We show that fusion of five feature-sets including domains, Position Specific Scoring Matrix-400, cellular compartments level one, and composition pairs with two and one gaps provide the best discrimination with an average correct classification rate of 77%. Conclusions We study a variety of known biological feature-sets of the proteins and show that there is a relation between domains, Position Specific Scoring Matrix-400, cellular compartments level one, composition pairs with two and one gaps of Saccharomyces Cerevisiae's proteins, and their roles in the protein interaction network as non-hubs, intermediately connected, party hubs and date hubs. This study also confirms the

  10. Effective spectral dimension of hub in scale-free networks

    Science.gov (United States)

    Hwang, Sungmin; Lee, Deok-Sun; Kahng, Byungnam

    2012-02-01

    Exploring the World Wide Web has become one of the key issues in information science, specifically in context of its application to the PageRank-like algorithms used in search engine. The random walk approach has been employed to study such a problem. The probability of the return to the origin (RTO) of random walks is inversely related to how information can be accessed during random surfing. We find analytically that the RTO probability for a given starting node shows a crossover from a slow to a fast decay behavior with time and the crossover time increases with the degree of the starting node. Furthermore, the RTO probability is almost constant in the early-time regime as the degree exponent approaches two. This result indicates that a random surfer can be effectively trapped at the hub and supports the necessity of the random jump strategy empirically used in the Google's search engine.

  11. Paneth cells: the hub for sensing and regulating intestinal flora.

    Science.gov (United States)

    Zhang, Zheng; Liu, Zhihua

    2016-05-01

    The complex interplay between symbiotic bacteria and host immunity plays a key role in shaping intestinal homeostasis and maintaining host health. Paneth cells, as one of the major producers of antimicrobial peptides in the intestine under steady-state conditions, play a vital role in regulating intestinal flora. Many studies on inflammatory bowel disease (IBD)-associated genes have put Paneth cells at the center of IBD pathogenesis. In this perspective, we focus on mechanistic studies of different cellular processes in Paneth cells that are regulated by various IBD-associated susceptibility genes, and we discuss the hypothesis that Paneth cells function as the central hub for sensing and regulating intestinal flora in the maintenance of intestinal homeostasis.

  12. A Collaborative Scheduling Model for the Supply-Hub with Multiple Suppliers and Multiple Manufacturers

    Directory of Open Access Journals (Sweden)

    Guo Li

    2014-01-01

    Full Text Available This paper investigates a collaborative scheduling model in the assembly system, wherein multiple suppliers have to deliver their components to the multiple manufacturers under the operation of Supply-Hub. We first develop two different scenarios to examine the impact of Supply-Hub. One is that suppliers and manufacturers make their decisions separately, and the other is that the Supply-Hub makes joint decisions with collaborative scheduling. The results show that our scheduling model with the Supply-Hub is a NP-complete problem, therefore, we propose an auto-adapted differential evolution algorithm to solve this problem. Moreover, we illustrate that the performance of collaborative scheduling by the Supply-Hub is superior to separate decision made by each manufacturer and supplier. Furthermore, we also show that the algorithm proposed has good convergence and reliability, which can be applicable to more complicated supply chain environment.

  13. Hub Identification of the Metro Manila Road Network Using PageRank

    CERN Document Server

    Chan, Jacob

    2016-01-01

    We attempt to identify the different node hubs of a road network using PageRank for preparation for possible random terrorist attacks. The robustness of a road network against such attack is crucial to be studied because it may cripple its connectivity by simply shutting down these hubs. We show the important hubs in a road network based on network structure and propose a model for robustness analysis. By identifying important hubs in a road network, possible preparation schemes may be done earlier to mitigate random terrorist attacks, including defense reinforcement and transportation security. A case study of the Metro Manila road network is also presented. The case study shows that the most important hubs in the Metro Manila road network are near airports, piers, major highways and expressways

  14. A Fractal and Scale-free Model of Complex Networks with Hub Attraction Behaviors

    CERN Document Server

    Kuang, Li; Li, Deyi; Li, Yuanxiang; Sun, Yu

    2013-01-01

    It is widely believed that fractality of complex networks origins from hub repulsion behaviors (anticorrelation or disassortativity), which means large degree nodes tend to connect with small degree nodes. This hypothesis was demonstrated by a dynamical growth model, which evolves as the inverse renormalization procedure proposed by Song et al. Now we find that the dynamical growth model is based on the assumption that all the cross-boxes links has the same probability e to link to the most connected nodes inside each box. Therefore, we modify the growth model by adopting the flexible probability e, which makes hubs have higher probability to connect with hubs than non-hubs. With this model, we find some fractal and scale-free networks have hub attraction behaviors (correlation or assortativity). The results are the counter-examples of former beliefs.

  15. MODELS AND METHODS FOR LOGISTICS HUB LOCATION: A REVIEW TOWARDS TRANSPORTATION NETWORKS DESIGN

    Directory of Open Access Journals (Sweden)

    Carolina Luisa dos Santos Vieira

    Full Text Available ABSTRACT Logistics hubs affect the distribution patterns in transportation networks since they are flow-concentrating structures. Indeed, the efficient moving of goods throughout supply chains depends on the design of such networks. This paper presents a literature review on the logistics hub location problem, providing an outline of modeling approaches, solving techniques, and their applicability to such context. Two categories of models were identified. While multi-criteria models may seem best suited to find optimal locations, they do not allow an assessment of the impact of new hubs on goods flow and on the transportation network. On the other hand, single-criterion models, which provide location and flow allocation information, adopt network simplifications that hinder an accurate representation of the relationshipbetween origins, destinations, and hubs. In view of these limitations we propose future research directions for addressing real challenges of logistics hubs location regarding transportation networks design.

  16. Electricity hubs and market centers: A new business tool for electric utilities?

    Energy Technology Data Exchange (ETDEWEB)

    Vallen, M.A.; Sharp, L.S. [Univ. of Toledo, OH (United States)

    1995-07-01

    There are many complexities clouding the use of hubs and market centers in the electricity market, but lessons learned in the natural gas industry can save a lot of unnecessary reinvention. The bottom line: Electricity hubs and market centers will allow the markets to work most efficiently. This article will describe how regional trading hubs may function in the competitive electricity market, using the experiences of the natural gas market to illustrate the principles involved. Part I will define the typical characteristics of hubs and market centers and describe the dey success factors needed to develop a new market center. Part II will describe the types of products and services that an electricity hub or marketing center will need to offer to succeed.

  17. VALUATION TECHNIQUES USED IN FAIR VALUE MEASUREMENT

    OpenAIRE

    Cristina-Aurora, BUNEA-BONTAS

    2013-01-01

    Valuation of assets and liabilities involves significant judgements and estimates, especially when fair value measurement is required. Currently, IFRS 13 Fair Value Measurement offers a single and more comprehensive source of guidance that is applied to almost all fair value estimates. When measuring fair value of fixed assets, intangible assets, specified financial assets or liabilities, different valuation techniques may be used: the market approach, the cost approach and the income appr...

  18. Job Fair for Foreigners,Beijing,2007

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The Job Fair for Foreigners, to be held in Beijing on April 21, is in its planning stage. Last year’s job fair was held in the Swissotel Beijing and plans are underway to reserve the hotel again for this year’s fair.Chinajob.com, as the host of the previous four job fairs, will continue to sponsor the fifth event especially for foreign teachers

  19. Covariance analysis of differential drag-based satellite cluster flight

    Science.gov (United States)

    Ben-Yaacov, Ohad; Ivantsov, Anatoly; Gurfil, Pini

    2016-06-01

    One possibility for satellite cluster flight is to control relative distances using differential drag. The idea is to increase or decrease the drag acceleration on each satellite by changing its attitude, and use the resulting small differential acceleration as a controller. The most significant advantage of the differential drag concept is that it enables cluster flight without consuming fuel. However, any drag-based control algorithm must cope with significant aerodynamical and mechanical uncertainties. The goal of the current paper is to develop a method for examination of the differential drag-based cluster flight performance in the presence of noise and uncertainties. In particular, the differential drag control law is examined under measurement noise, drag uncertainties, and initial condition-related uncertainties. The method used for uncertainty quantification is the Linear Covariance Analysis, which enables us to propagate the augmented state and filter covariance without propagating the state itself. Validation using a Monte-Carlo simulation is provided. The results show that all uncertainties have relatively small effect on the inter-satellite distance, even in the long term, which validates the robustness of the used differential drag controller.

  20. Simplified Models for the Drag Coefficient of a Pitched Baseball

    Science.gov (United States)

    Kagan, David; Nathan, Alan M.

    2014-01-01

    The classic experiment to measure the drag coefficient involves dropping coffee filters. Wouldn't it be more fun to try something different? In fact, an experiment on the drag force is conducted nearly 4000 times a day during the baseball season and you have free access to this PITCHf/x data!

  1. Drag reduction through self-texturing compliant bionic materials

    Science.gov (United States)

    Liu, Eryong; Li, Longyang; Wang, Gang; Zeng, Zhixiang; Zhao, Wenjie; Xue, Qunji

    2017-01-01

    Compliant fish skin is effectively in reducing drag, thus the design and application of compliant bionic materials may be a good choice for drag reduction. Here we consider the drag reduction of compliant bionic materials. First, ZnO and PDMS mesh modified with n-octadecane were prepared, the drag reduction of self-texturing compliant n-octadecane were studied. The results show that the mesh modified by ZnO and PDMS possess excellent lipophilic and hydrophobic, thus n-octadecane at solid, semisolid and liquid state all have good adhesion with modified mesh. The states of n-octadecane changed with temperature, thus, the surface contact angle and adhesive force all varies obviously at different state. The contact angle decreases with temperature, the adhesive force shows a lower value at semisolid state. Furthermore, the drag testing results show that the compliant n-octadecane film is more effectively in drag reduction than superhydrophobic ZnO/PDMS film, indicating that the drag reduction mechanism of n-octadecane is significantly different with superhydrophobic film. Further research shows that the water flow leads to self-texturing of semisolid state n-octadecane, which is similar with compliant fish skin. Therefore, the compliant bionic materials of semisolid state n-octadecane with regular bulge plays a major role in the drag reduction.

  2. Bionic Research on Fish Scales for Drag Reduction

    Institute of Scientific and Technical Information of China (English)

    Zhaoliang Dou; Jiadao Wang; Darong Chen

    2012-01-01

    To reduce friction drag with bionic method in a more feasible way,the surface microstructure of fish scales was analyzed attempting to reveal the biologic features responding to skin friction drag reduction.Then comparable bionic surface mimicking fish scales was fabricated through coating technology for drag reduction.The paint mixture was coated on a substrate through a self-developed spray-painting apparatus.The bionic surface with micron-scale caves formed spontaneously due to the interfacial convection and deformation driven by interfacial tension gradient in the presence of solvent evaporation.Comparative experiments between bionic surface and smooth surface were performed in a water tunnel to evaluate the effect of bionic surface on drag reduction,and visible drag reduction efficiency was obtained.Numerical simulation results show that gas phase develops in solid-liquid interface of bionic surface with the effect of surface topography and partially replaces the solid-liquid shear force with gas-liquid shear force,hence reducing the skin friction drag effectively.Therefore,with remarkable drag reduction performance and simple fabrication technology,the proposed drag reduction technique shows the promise for practical applications.

  3. Drag reduction in turbulent MHD pipe flows

    Science.gov (United States)

    Orlandi, P.

    1996-01-01

    This is a preliminary study devoted to verifying whether or not direct simulations of turbulent Magneto-Hydro-Dynamic (MHD) flows in liquid metals reproduce experimental observations of drag reduction. Two different cases have been simulated by a finite difference scheme which is second order accurate in space and time. In the first case, an external azimuthal magnetic field is imposed. In this case, the magnetic field acts on the mean axial velocity and complete laminarization of the flow at N(sub a) = 30 has been achieved. In the second case, an axial magnetic field is imposed which affects only fluctuating velocities, and thus the action is less efficient. This second case is more practical, but comparison between numerical and experimental results is only qualitative.

  4. Lift and drag of cetacean flippers

    Science.gov (United States)

    Murray, Mark; Weber, Paul; Howle, Laurens; Fish, Frank

    2008-11-01

    Field observation and collection of biological samples has resulted in cetacean (whales, dolphins and porpoises) flipper geometry being known for most species. However, the hydrodynamic properties of cetacean flippers have not been rigorously tested and thus their performance characteristics are unknown. Here, conducting water tunnel testing using scale models of cetacean flippers derived via computed tomography (CT) scans, as well as computational fluid dynamic (CFD) simulations, we present a baseline work to determine the hydrodynamic characteristics of cetacean flippers. We found that flippers of similar planform shape had similar hydrodynamic performance characteristics. Furthermore, one group of flippers of planform shape similar to a modern swept wing was found to have lift coefficient versus angle of attack curves that were biphasic rather than linear in nature, which was caused by the onset of vortex-dominated lift. Drag coefficient versus angle of attack curves were found to be less dependant on planform shape.

  5. Dancing droplets: Contact angle, drag, and confinement

    Science.gov (United States)

    Benusiglio, Adrien; Cira, Nate; Prakash, Manu

    2015-11-01

    When deposited on a clean glass slide, a mixture of water and propylene glycol forms a droplet of given contact angle, when both pure liquids spread. (Cira, Benusiglio, Prakash: Nature, 2015). The droplet is stabilized by a gradient of surface tension due to evaporation that induces a Marangoni flow from the border to the apex of the droplets. The apparent contact angle of the droplets depends on both their composition and the external humidity as captured by simple models. These droplets present remarkable properties such as lack of a large pinning force. We discuss the drag on these droplets as a function of various parameters. We show theoretical and experimental results of how various confinement geometries change the vapor gradient and the dynamics of droplet attraction.

  6. Analytical Ballistic Trajectories with Approximately Linear Drag

    Directory of Open Access Journals (Sweden)

    Giliam J. P. de Carpentier

    2014-01-01

    Full Text Available This paper introduces a practical analytical approximation of projectile trajectories in 2D and 3D roughly based on a linear drag model and explores a variety of different planning algorithms for these trajectories. Although the trajectories are only approximate, they still capture many of the characteristics of a real projectile in free fall under the influence of an invariant wind, gravitational pull, and terminal velocity, while the required math for these trajectories and planners is still simple enough to efficiently run on almost all modern hardware devices. Together, these properties make the proposed approach particularly useful for real-time applications where accuracy and performance need to be carefully balanced, such as in computer games.

  7. 7 CFR 51.1553 - Fairly clean.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Fairly clean. 51.1553 Section 51.1553 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Standards for Grades of Potatoes 1 Definitions § 51.1553 Fairly clean. Fairly clean means that at least...

  8. 7 CFR 51.1581 - Fairly clean.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Fairly clean. 51.1581 Section 51.1581 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Consumer Standards for Potatoes Definitions § 51.1581 Fairly clean. Fairly clean means that from...

  9. 7 CFR 51.2965 - Fairly clean.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Fairly clean. 51.2965 Section 51.2965 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Standards for Grades of Walnuts in the Shell Definitions § 51.2965 Fairly clean. Fairly clean means...

  10. 17th Dalian International Garment Fair

    Institute of Scientific and Technical Information of China (English)

    Bai Yifeng

    2005-01-01

    @@ Basic Information of 17th Dalian International Garment Fair The 17th Dalian International Garment Fair will be held from September 10 to 13, 2005at Xinghai Convention and Exhibition Center (old hall) and newly-built World Expo Square(new hall) simultaneously. The fair area is about 50,000 m2, 2.5 times than the last one.

  11. Fairness and Using Reflective Journals in Assessment

    Science.gov (United States)

    Clarkeburn, Henriikka; Kettula, Kirsi

    2012-01-01

    This study looks at the fairness of assessing learning journals both as the fairness in creating a valid and robust marking process as well as how different student groups may have unfair disadvantages in performing well in reflective assessment tasks. The fairness of a marking process is discussed through reflecting on the practical process and…

  12. Test Fairness and Toulmin's Argument Structure

    Science.gov (United States)

    Kunnan, Antony John

    2010-01-01

    This paper presents the author's response to Xiaoming Xi's article titled "How do we go about investigating test fairness?" In this response, the author focuses on test fairness and Toulmin's model of argument structure, Xi's proposal, and the challenges the proposal brings. Xi proposes an approach to investigating test fairness to guide…

  13. A Science Fair Companion. ERIC Digest.

    Science.gov (United States)

    McCann, Wendy Sherman

    This digest comments on various aspects of school science fairs. General expectations for science fair projects and participants are discussed, and tips for choosing a topic and completing a project are given. Organizational strategies for teachers charged with conducting science fairs are presented. Guidelines for parents in helping children with…

  14. Sex Fair Grading in Physical Education.

    Science.gov (United States)

    Deutsch, Helga

    1984-01-01

    Sex fair performance evaluation has been a primary concern in physical education. A discussion of physiological differences between males and females shows how problems in developing fair evaluation plans arise. Suggestions for developing a sex fair grading plan and an example program adaptable to other settings are offered. (DF)

  15. Shanghai Performing Arts Fair Gaining Global Popularity

    Institute of Scientific and Technical Information of China (English)

    TianZui; ZuZhongren

    2003-01-01

    China Shanghai International Arts Festival Performing Arts Fair is gaining popularity. In two months after the dates of the fair were announced, all the 120 booths were booked out, and for the first time in the event's four-year history, participants had to scramble to get in. When the trade fair opened, about 40 organizations were shut out.

  16. 15th Beijing International Book Fair

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The 15th Beijing Intemational Book Fair(BIBF)is to be held in Tianjin on September 1-4.It is the first time that the fair is held outside of Beijing. The change of venue is because the book fair coincides with the closing of the Beijing Olympic Games and the open-

  17. Do fair value adjustments influence dividend policy?

    NARCIS (Netherlands)

    Goncharov, I.; van Triest, S.

    2011-01-01

    We examine the impact of positive fair value adjustments on dividend policy. If fair value adjustments are transitory in nature and managers are able to assess their implications for future earnings, fair value adjustments in net income is expected to have no distribution consequences. However, posi

  18. Playing Fair: An Essential Element in Contracting

    Science.gov (United States)

    Peeler, Tom

    2012-01-01

    Playing fair has a value with which people are all familiar. From the sandboxes of childhood and the competitive sports of youth to the business transactions of adulthood, people have been told how important it is to play fair. Playing fair in contracting is not only essential, it's the legal and ethical thing to do. In this article, the author…

  19. faire faire 》 et 《 se faire faire 》-- Analyse sur les emplois de la construction 《 faire+incnitif 》

    Institute of Scientific and Technical Information of China (English)

    任志勇

    2011-01-01

    Le verbe faire relève parfois des r6gles de syntaxe grammaticale, le faire causatif. Quand le verbe faire est suivi d'un innitif, sa construction est spèciale parce que les règles qui gouvernent l'emploi et la place des pronoms et des noms complèments d'o

  20. Do fair value adjustments influence dividend policy?

    NARCIS (Netherlands)

    Goncharov, I.; van Triest, S.

    2011-01-01

    We examine the impact of positive fair value adjustments on dividend policy. If fair value adjustments are transitory in nature and managers are able to assess their implications for future earnings, fair value adjustments in net income is expected to have no distribution consequences. However,

  1. USDA Southwest Regional Hub for Adaptation to and Mitigation of Climate Change

    Science.gov (United States)

    Rango, A.; Elias, E.; Steele, C. M.; Havstad, K.

    2014-12-01

    The USDA Southwest (SW) Climate Hub was created in February 2014 to develop risk adaptation and mitigation strategies for coping with climate change effects on agricultural productivity. There are seven regional hubs across the country with three subsidiary hubs. The SW Climate Hub Region is made up of six states: New Mexico, Arizona, Utah, Nevada, California and Hawaii (plus the Trust Territories of the Pacific Islands). The SW Climate Hub has a subsidiary hub located in Davis, California. The Southwest region has high climatic diversity, with the lowest and highest average annual rainfall in the U.S.(6.0 cm in Death Valley, CA and 1168 cm at Mt. Waialeale, HI). There are major deserts in five of the six states, yet most of the states, with exception of Hawaii, depend upon the melting of mountain snowpacks for their surface water supply. Additionally, many of the agricultural areas of the SW Regional Hub depend upon irrigation water to maintain productivity. Scientific climate information developed by the Hub will be used for climate-smart decision making. To do this, the SW Regional Hub will rely upon existing infrastructure of the Cooperative Extension Service at Land-Grant State Universities. Extension service and USDA-NRCS personnel have existing networks to communicate with stakeholders (farmers, ranchers, and forest landowners) through meetings and workshops which have already started in the six states. Outreach through the development of a weather and climate impact modules designed for seventh grade students and their teachers will foster education of future generations of rural land managers. We will be synthesizing and evaluating existing reports, literature and information on regional climate projections, water resources, and agricultural adaptation strategies related to climate in the Southwest. The results will be organized in a spatial format and provided through the SW Hub website (http://swclimatehub.info) and peer-reviewed articles.

  2. The noise generated by a landing gear wheel with hub and rim cavities

    Science.gov (United States)

    Wang, Meng; Angland, David; Zhang, Xin

    2017-03-01

    Wheels are one of the major noise sources of landing gears. Accurate numerical predictions of wheel noise can provide an insight into the physical mechanism of landing gear noise generation and can aid in the design of noise control devices. The major noise sources of a 33% scaled isolated landing gear wheel are investigated by simulating three different wheel configurations using high-order numerical simulations to compute the flow field and the FW-H equation to obtain the far-field acoustic pressures. The baseline configuration is a wheel with a hub cavity and two rim cavities. Two additional simulations are performed; one with the hub cavity covered (NHC) and the other with both the hub cavity and rim cavities covered (NHCRC). These simulations isolate the effects of the hub cavity and rim cavities on the overall wheel noise. The surface flow patterns are visualised by shear stress lines and show that the flow separations and attachments on the side of the wheel, in both the baseline and the configuration with only the hub cavity covered, are significantly reduced by covering both the hub and rim cavities. A frequency-domain FW-H equation is used to identify the noise source regions on the surface of the wheel. The tyre is the main low frequency noise source and shows a lift dipole and side force dipole pattern depending on the frequency. The hub cavity is identified as the dominant middle frequency noise source and radiates in a frequency range centered around the first and second depth modes of the cylindrical hub cavity. The rim cavities are the main high-frequency noise sources. With the hub cavity and rim cavities covered, the largest reduction in Overall Sound Pressure Level (OASPL) is achieved in the hub side direction. In the other directivities, there is also a reduction in the radiated sound.

  3. Air Flows in Gravity Sewers - Determination of Wastewater Drag Coefficient

    DEFF Research Database (Denmark)

    Bentzen, Thomas Ruby; Østertoft, Kristian; Vollertsen, Jes

    2016-01-01

    of the study shows that by integrating the top/side wall shear stresses the log-law models for the air velocity distribution along the unwetted perimeter resulted in a good agreement with the friction forces calculated by use of the Colebrook-White formula for hydraulic smooth pipes. Secondly, the water......Several experiments have been conducted in order to improve the understanding of the wastewater drag and the wall frictional force acting on the headspace air in gravity sewers. The aim of the study is to improve the data basis for a numerical model of natural sewer ventilation. The results...... surface drags were found by log-law models of the velocity distribution in turbulent flows to fit velocity profiles measured from the water surface and by integrating the water surface drags along the wetted perimeter, mean water surface drags were found and a measure of the water surface drag coefficient...

  4. Collisional Effects on Nonlinear Ion Drag Force for Small Grains

    CERN Document Server

    Hutchinson, I H

    2013-01-01

    The ion drag force arising from plasma flow past an embedded spherical grain is calculated self-consistently and non-linearly using particle in cell codes, accounting for ion-neutral collisions. Using ion velocity distribution appropriate for ion drift driven by a force field gives wake potential and force greatly different from a shifted Maxwellian distribution, regardless of collisionality. The low-collisionality forces are shown to be consistent with estimates based upon cross-sections for scattering in a Yukawa (shielded) grain field, but only if non-linear shielding length is used. Finite collisionality initially enhances the drag force, but only by up to a factor of 2. Larger collisionality eventually reduces the drag force. In the collisional regime, the drift distribution gives larger drag than the shift distribution even at velocities where their collisionless drags are equal. Comprehensive practical analytic formulas for force that fit the calculations are provided.

  5. Methods for Accurate Free Flight Measurement of Drag Coefficients

    CERN Document Server

    Courtney, Elya; Courtney, Michael

    2015-01-01

    This paper describes experimental methods for free flight measurement of drag coefficients to an accuracy of approximately 1%. There are two main methods of determining free flight drag coefficients, or equivalent ballistic coefficients: 1) measuring near and far velocities over a known distance and 2) measuring a near velocity and time of flight over a known distance. Atmospheric conditions must also be known and nearly constant over the flight path. A number of tradeoffs are important when designing experiments to accurately determine drag coefficients. The flight distance must be large enough so that the projectile's loss of velocity is significant compared with its initial velocity and much larger than the uncertainty in the near and/or far velocity measurements. On the other hand, since drag coefficients and ballistic coefficients both depend on velocity, the change in velocity over the flight path should be small enough that the average drag coefficient over the path (which is what is really determined)...

  6. Drag coefficient for the air-sea exchange: foam impact in hurricane conditions

    CERN Document Server

    Golbraikh, Ephim

    2014-01-01

    A physical model is proposed for the estimation of the foam impact on the variation of the effective drag coefficient, C_d, with reference to the wind speed U10 in stormy and hurricane conditions. In the present model C_d is approximated by partitioning the sea surface into foam-covered and foam-free areas. Based on the available optical and radiometric measurements of the fractional foam coverage and the characteristic roughness of the sea-surface in the saturation limit of the foam coverage, the model yields the resulting dependence of C_d vs U10. This dependence is in fair agreement with that evaluated from field measurements of the vertical variation of the mean wind speed.

  7. 75 FR 4100 - Affirmative Fair Housing, Marketing (AFHM) Plan-Multifamily Housing, Affirmative Fair Housing...

    Science.gov (United States)

    2010-01-26

    ... URBAN DEVELOPMENT Affirmative Fair Housing, Marketing (AFHM) Plan-Multifamily Housing, Affirmative Fair Housing Marketing (AFHM) Plan-Single Family Housing and Affirmative Fair Housing Marketing (AFHM) Plan... lists the following information: Title of Proposal: Affirmative Fair Housing, Marketing (AFHM) Plan...

  8. Book Review: Is Fair Value Fair? Financial Reporting from an International Perspective

    DEFF Research Database (Denmark)

    Thinggaard, Frank

    2005-01-01

    This is a review of Henk Langendijk, Dirk Swagerman and Willem Verhoog (Eds) "Is Fair Value Fair? Financial Reporting from an International Perspective," Chichester: John Wiley, 2003, ISBN 0 470 85028 0.......This is a review of Henk Langendijk, Dirk Swagerman and Willem Verhoog (Eds) "Is Fair Value Fair? Financial Reporting from an International Perspective," Chichester: John Wiley, 2003, ISBN 0 470 85028 0....

  9. 75 FR 18245 - Public Federal Regulatory Enforcement Fairness Hearing Region IX Regulatory Fairness Board

    Science.gov (United States)

    2010-04-09

    ... ADMINISTRATION Public Federal Regulatory Enforcement Fairness Hearing Region IX Regulatory Fairness Board.... Small Business Administration (SBA) Region IX Regulatory Fairness Board and the SBA Office of the National Ombudsman will hold a National Regulatory Fairness Hearing on Monday, April 26, 2010, at 1:30 p.m...

  10. 78 FR 30384 - Federal Regulatory Enforcement Fairness Hearing; Region X Regulatory Fairness Board

    Science.gov (United States)

    2013-05-22

    ... ADMINISTRATION Federal Regulatory Enforcement Fairness Hearing; Region X Regulatory Fairness Board AGENCY: U.S... Business Regulatory Fairness Board. SUMMARY: The (SBA) Office of the National Ombudsman is issuing this notice to announce the location, date and time of the Regional Small Business Regulatory Fairness hearing...

  11. 75 FR 17793 - Public Federal Regulatory Enforcement Fairness Hearing; Region III Regulatory Fairness Board

    Science.gov (United States)

    2010-04-07

    ... ADMINISTRATION Public Federal Regulatory Enforcement Fairness Hearing; Region III Regulatory Fairness Board.... Small Business Administration (SBA) Region III Regulatory Fairness Board and the SBA Office of the National Ombudsman will hold a National Regulatory Fairness Hearing on Tuesday, May 18, 2010, at 10 a.m...

  12. 78 FR 36011 - Region VII Regulatory Fairness Board; Federal Regulatory Enforcement Fairness Hearing

    Science.gov (United States)

    2013-06-14

    ... ADMINISTRATION Region VII Regulatory Fairness Board; Federal Regulatory Enforcement Fairness Hearing AGENCY: U.S... Business Regulatory Fairness Board. SUMMARY: The (SBA) Office of the National Ombudsman is issuing this notice to announce the location, date and time of the Regional Small Business Regulatory Fairness hearing...

  13. 76 FR 26333 - National Federal Regulatory Enforcement Fairness Hearing Region III Regulatory Fairness Board

    Science.gov (United States)

    2011-05-06

    ... ADMINISTRATION National Federal Regulatory Enforcement Fairness Hearing Region III Regulatory Fairness Board... III) Small Business Regulatory Fairness Board. SUMMARY: The SBA, Office of the National Ombudsman is... Fairness Hearing. This hearing is open to the public. DATES: The hearing will be held on Tuesday, May 24...

  14. Generalized fairing algorithm of parametric cubic splines

    Institute of Scientific and Technical Information of China (English)

    WANG Yuan-jun; CAO Yuan

    2006-01-01

    Kjellander has reported an algorithm for fairing uniform parametric cubic splines. Poliakoff extended Kjellander's algorithm to non-uniform case. However, they merely changed the bad point's position, and neglected the smoothing of tangent at bad point. In this paper, we present a fairing algorithm that both changed point's position and its corresponding tangent vector. The new algorithm possesses the minimum property of energy. We also proved Poliakoff's fairing algorithm is a deduction of our fairing algorithm. Several fairing examples are given in this paper.

  15. Hyperons at CBM-FAIR

    Science.gov (United States)

    Schmidt, Hans Rudolf

    2016-08-01

    The CBM experiment is one of the four scientific pillars of the Facility for Antiprotons and Ion Research (FAIR) in Darmstadt, Germany. Its discovery potential - complementary to heavy-ion experiments at colliders - is based on high-luminosity ion beams. This enables access to extremely rare probes such as charmed particles, vector mesons or multi-strange hyperons with high statistics. However, 3rd generations readout systems and detectors are required to handle the large interaction rates (up to 10 MHz for Au+Au) with sufficient precision and bandwidth. In this contribution we will outline the unique CBM physics program focusing onto hyperons.

  16. Connectome hubs at resting state in children and adolescents: Reproducibility and psychopathological correlation

    Directory of Open Access Journals (Sweden)

    João Ricardo Sato

    2016-08-01

    Full Text Available Functional brain hubs are key integrative regions in brain networks. Recently, brain hubs identified through resting-state fMRI have emerged as interesting targets to increase understanding of the relationships between large-scale functional networks and psychopathology. However, few studies have directly addressed the replicability and consistency of the hub regions identified and their association with symptoms. Here, we used the eigenvector centrality (EVC measure obtained from graph analysis of two large, independent population-based samples of children and adolescents (7–15 years old; total N = 652; 341 subjects for site 1 and 311 for site 2 to evaluate the replicability of hub identification. Subsequently, we tested the association between replicable hub regions and psychiatric symptoms. We identified a set of hubs consisting of the anterior medial prefrontal cortex and inferior parietal lobule/intraparietal sulcus (IPL/IPS. Moreover, lower EVC values in the right IPS were associated with psychiatric symptoms in both samples. Thus, low centrality of the IPS was a replicable sign of potential vulnerability to mental disorders in children. The identification of critical and replicable hubs in functional cortical networks in children and adolescents can foster understanding of the mechanisms underlying mental disorders.

  17. Connectome hubs at resting state in children and adolescents: Reproducibility and psychopathological correlation.

    Science.gov (United States)

    Sato, João Ricardo; Biazoli, Claudinei Eduardo; Salum, Giovanni Abrahão; Gadelha, Ary; Crossley, Nicolas; Vieira, Gilson; Zugman, André; Picon, Felipe Almeida; Pan, Pedro Mario; Hoexter, Marcelo Queiroz; Anés, Mauricio; Moura, Luciana Monteiro; Del'Aquilla, Marco Antonio Gomes; Junior, Edson Amaro; Mcguire, Philip; Rohde, Luis Augusto; Miguel, Euripedes Constantino; Bressan, Rodrigo Affonseca; Jackowski, Andrea Parolin

    2016-08-01

    Functional brain hubs are key integrative regions in brain networks. Recently, brain hubs identified through resting-state fMRI have emerged as interesting targets to increase understanding of the relationships between large-scale functional networks and psychopathology. However, few studies have directly addressed the replicability and consistency of the hub regions identified and their association with symptoms. Here, we used the eigenvector centrality (EVC) measure obtained from graph analysis of two large, independent population-based samples of children and adolescents (7-15 years old; total N=652; 341 subjects for site 1 and 311 for site 2) to evaluate the replicability of hub identification. Subsequently, we tested the association between replicable hub regions and psychiatric symptoms. We identified a set of hubs consisting of the anterior medial prefrontal cortex and inferior parietal lobule/intraparietal sulcus (IPL/IPS). Moreover, lower EVC values in the right IPS were associated with psychiatric symptoms in both samples. Thus, low centrality of the IPS was a replicable sign of potential vulnerability to mental disorders in children. The identification of critical and replicable hubs in functional cortical networks in children and adolescents can foster understanding of the mechanisms underlying mental disorders.

  18. Incremental Optimization of Hub and Spoke Network for the Spokes’ Numbers and Flow

    Directory of Open Access Journals (Sweden)

    Yanfeng Wang

    2015-01-01

    Full Text Available Hub and spoke network problem is solved as part of a strategic decision making process which may have a profound effect on the future of enterprises. In view of the existing network structure, as time goes on, the number of spokes and the flow change because of different sources of uncertainty. Hence, the incremental optimization of hub and spoke network problem is considered in this paper, and the policy makers should adopt a series of strategies to cope with the change, such as setting up new hubs, adjusting the capacity level of original hubs, or closing some original hubs. The objective is to minimize the total cost, which includes the setup costs for the new hubs, the closure costs, and the adjustment costs for the original hubs as well as the flow routing costs. Two mixed-integer linear programming formulations are proposed and analyzed for this problem. China Deppon Logistics as an example is performed to present computational analysis, and we analyze the changes in the solutions driven by the number of spokes and the flow. The tests also allow an analysis to consider the effect of variation in parameters on network.

  19. Fatigue based design and analysis of wheel hub for Student formula car by Simulation Approach

    Science.gov (United States)

    Gowtham, V.; Ranganathan, A. S.; Satish, S.; Alexis, S. John; Siva kumar, S.

    2016-09-01

    In the existing design of Wheel hub used for Student formula cars, the brake discs cannot be removed easily since the disc is mounted in between the knuckle and hub. In case of bend or any other damage to the disc, the replacement of the disc becomes difficult. Further using OEM hub and knuckle that are used for commercial vehicles will result in increase of unsprung mass, which should be avoided in Student formula cars for improving the performance. In this design the above mentioned difficulties have been overcome by redesigning the hub in such a way that the brake disc could be removed easily by just removing the wheel and the caliper and also it will have reduced weight when compared to existing OEM hub. A CAD Model was developed based on the required fatigue life cycles. The forces acting on the hub were calculated and linear static structural analysis was performed on the wheel hub for three different materials using ANSYS Finite Element code V 16.2. The theoretical fatigue strength was compared with the stress obtained from the structural analysis for each material.

  20. A multidomain hub anchors the chromosome segregation and chemotactic machinery to the bacterial pole.

    Science.gov (United States)

    Yamaichi, Yoshiharu; Bruckner, Raphael; Ringgaard, Simon; Möll, Andrea; Cameron, D Ewen; Briegel, Ariane; Jensen, Grant J; Davis, Brigid M; Waldor, Matthew K

    2012-10-15

    The cell poles constitute key subcellular domains that are often critical for motility, chemotaxis, and chromosome segregation in rod-shaped bacteria. However, in nearly all rods, the processes that underlie the formation, recognition, and perpetuation of the polar domains are largely unknown. Here, in Vibrio cholerae, we identified HubP (hub of the pole), a polar transmembrane protein conserved in all vibrios, that anchors three ParA-like ATPases to the cell poles and, through them, controls polar localization of the chromosome origin, the chemotactic machinery, and the flagellum. In the absence of HubP, oriCI is not targeted to the cell poles, chemotaxis is impaired, and a small but increased fraction of cells produces multiple, rather than single, flagella. Distinct cytoplasmic domains within HubP are required for polar targeting of the three ATPases, while a periplasmic portion of HubP is required for its localization. HubP partially relocalizes from the poles to the mid-cell prior to cell division, thereby enabling perpetuation of the polar domain in future daughter cells. Thus, a single polar hub is instrumental for establishing polar identity and organization.

  1. Hubs and authorities in the world trade network using a weighted HITS algorithm.

    Science.gov (United States)

    Deguchi, Tsuyoshi; Takahashi, Katsuhide; Takayasu, Hideki; Takayasu, Misako

    2014-01-01

    We investigate the economic hubs and authorities of the world trade network (WTN) from 1992 to 2012, an era of rapid economic globalization. Using a well-defined weighted hyperlink-induced topic search (HITS) algorithm, we can calculate the values of the weighted HITS hub and authority for each country in a conjugate way. In the context of the WTN, authority values are large for countries with significant imports from large hub countries, and hub values are large for countries with significant exports to high-authority countries. The United States was the largest economic authority in the WTN from 1992 to 2012. The authority value of the United States has declined since 2001, and China has now become the largest hub in the WTN. At the same time, China's authority value has grown as China is transforming itself from the "factory of the world" to the "market of the world." European countries show a tendency to trade mostly within the European Union, which has decreased Europe's hub and authority values. Japan's authority value has increased slowly, while its hub value has declined. These changes are consistent with Japan's transition from being an export-driven economy in its high economic growth era in the latter half of the twentieth century to being a more mature, economically balanced nation.

  2. Hubs and authorities in the world trade network using a weighted HITS algorithm.

    Directory of Open Access Journals (Sweden)

    Tsuyoshi Deguchi

    Full Text Available We investigate the economic hubs and authorities of the world trade network (WTN from 1992 to 2012, an era of rapid economic globalization. Using a well-defined weighted hyperlink-induced topic search (HITS algorithm, we can calculate the values of the weighted HITS hub and authority for each country in a conjugate way. In the context of the WTN, authority values are large for countries with significant imports from large hub countries, and hub values are large for countries with significant exports to high-authority countries. The United States was the largest economic authority in the WTN from 1992 to 2012. The authority value of the United States has declined since 2001, and China has now become the largest hub in the WTN. At the same time, China's authority value has grown as China is transforming itself from the "factory of the world" to the "market of the world." European countries show a tendency to trade mostly within the European Union, which has decreased Europe's hub and authority values. Japan's authority value has increased slowly, while its hub value has declined. These changes are consistent with Japan's transition from being an export-driven economy in its high economic growth era in the latter half of the twentieth century to being a more mature, economically balanced nation.

  3. Inspired at a book fair

    CERN Multimedia

    Anaïs Schaeffer

    2012-01-01

    During the Frankfurt book fair last October, the CERN stand drew quite the crowd. Director-General Rolf Heuer was there to promote CERN’s mission and the "LHC: the Large Hadron Collider" book. He met a lot of visitors and for one of them there was also a nice follow-up…   Marcus and his father visiting the LINAC facility. Fifteen year-old Marcus lives in Lauterecken near Frankfurt. The popular book fair last autumn was for him a nice opportunity to get in touch with the CERN environment. Inspired by the stand and what the CERN people were describing, he started to ask more and more questions… So many, that Rolf Heuer decided to invite him to come to CERN and find out some of the answers for himself. A few weeks later, while recovering from an exciting visit to the ATLAS underground cavern and other CERN installations with a cup of tea in Restaurant 1, Marcus shared his enthusiasm about the Organization: “When I was younger, my moth...

  4. Fair pricing, and pricing paradoxes

    Directory of Open Access Journals (Sweden)

    Barbara Swart

    2016-05-01

    Full Text Available The St Petersburg Paradox revolves round the determination of a fair price for playing the St Petersburg Game. According to the original formulation, the price for the game is infinite, and, therefore, paradoxical. Although the St Petersburg Paradox can be seen as concerning merely a game, Paul Samuelson (1977 calls it a “fascinating chapter in the history of ideas”, a chapter that gave rise to a considerable number of papers over more than 200 years involving fields such as probability theory and economics. In a paper in this journal, Vivian (2013 undertook a numerical investigation of the St Petersburg Game. In this paper, the central issue of the paradox is identified as that of fair (risk-neutral pricing, which is fundamental in economics and finance and involves important concepts such as no arbitrage, discounting, and risk-neutral measures. The model for the St Petersburg Game as set out in this paper is new and analytical and resolves the so-called pricing paradox by applying a discounting procedure. In this framework, it is shown that there is in fact no infinite price paradox, and simple formulas for obtaining a finite price for the game are also provided.

  5. Experimental investigation of drag coefficients of gobi surfaces

    Institute of Scientific and Technical Information of China (English)

    董治宝; 屈建军; 刘小平; 张伟民; 王训明

    2002-01-01

    The response of gobi surfaces to the near-surface air flow can be characterized quantitatively by drag coefficients. By using wind tunnel tests, an attempt is made to define the relationship between the drag coefficients of gobi surfaces and gravel size and coverage. It is concluded that the drag coefficients of gobi surfaces tend to be constants when gravel coverage is over 40%-50%. Consequently, we think that the gobi deflation planes expanding vastly in the arid Northwestern China are aerodynamically stable, at least not the supplying sources of current dust storms, and therefore the emphasis on dust storm control should be paid on the so-called "earth gobi" that has low gravel coverage. The prediction model for drag coefficients of gobi surfaces has been developed by regressing drag coefficients on gravel size and coverage, the predicted results are in reasonably good agreement with wind tunnel results (R 2 = 0.94). The change of drag coefficients with gravel friction Reynolds number implies that the development extent of drag effect increases with gravel size and coverage.

  6. Variability of Bed Drag on Cohesive Beds under Wave Action

    Directory of Open Access Journals (Sweden)

    Ilgar Safak

    2016-04-01

    Full Text Available Drag force at the bed acting on water flow is a major control on water circulation and sediment transport. Bed drag has been thoroughly studied in sandy waters, but less so in muddy coastal waters. The variation of bed drag on a muddy shelf is investigated here using field observations of currents, waves, and sediment concentration collected during moderate wind and wave events. To estimate bottom shear stress and the bed drag coefficient, an indirect empirical method of logarithmic fitting to current velocity profiles (log-law, a bottom boundary layer model for combined wave-current flow, and a direct method that uses turbulent fluctuations of velocity are used. The overestimation by the log-law is significantly reduced by taking turbulence suppression due to sediment-induced stratification into account. The best agreement between the model and the direct estimates is obtained by using a hydraulic roughness of 10 - 4 m in the model. Direct estimate of bed drag on the muddy bed is found to have a decreasing trend with increasing current speed, and is estimated to be around 0.0025 in conditions where wave-induced flow is relatively weak. Bed drag shows an increase (up to fourfold with increasing wave energy. These findings can be used to test the bed drag parameterizations in hydrodynamic and sediment transport models and the skills of these models in predicting flows in muddy environments.

  7. Variability of bed drag on cohesive beds under wave action

    Science.gov (United States)

    Safak, Ilgar

    2016-01-01

    Drag force at the bed acting on water flow is a major control on water circulation and sediment transport. Bed drag has been thoroughly studied in sandy waters, but less so in muddy coastal waters. The variation of bed drag on a muddy shelf is investigated here using field observations of currents, waves, and sediment concentration collected during moderate wind and wave events. To estimate bottom shear stress and the bed drag coefficient, an indirect empirical method of logarithmic fitting to current velocity profiles (log-law), a bottom boundary layer model for combined wave-current flow, and a direct method that uses turbulent fluctuations of velocity are used. The overestimation by the log-law is significantly reduced by taking turbulence suppression due to sediment-induced stratification into account. The best agreement between the model and the direct estimates is obtained by using a hydraulic roughness of 10  m in the model. Direct estimate of bed drag on the muddy bed is found to have a decreasing trend with increasing current speed, and is estimated to be around 0.0025 in conditions where wave-induced flow is relatively weak. Bed drag shows an increase (up to fourfold) with increasing wave energy. These findings can be used to test the bed drag parameterizations in hydrodynamic and sediment transport models and the skills of these models in predicting flows in muddy environments.

  8. Drag reduction in turbulent flows over superhydrophobic surfaces

    Science.gov (United States)

    Daniello, Robert J.; Waterhouse, Nicholas E.; Rothstein, Jonathan P.

    2009-08-01

    In this paper, we demonstrate that periodic, micropatterned superhydrophobic surfaces, previously noted for their ability to provide laminar flow drag reduction, are capable of reducing drag in the turbulent flow regime. Superhydrophobic surfaces contain micro- or nanoscale hydrophobic features which can support a shear-free air-water interface between peaks in the surface topology. Particle image velocimetry and pressure drop measurements were used to observe significant slip velocities, shear stress, and pressure drop reductions corresponding to drag reductions approaching 50%. At a given Reynolds number, drag reduction is found to increase with increasing feature size and spacing, as in laminar flows. No observable drag reduction was noted in the laminar regime, consistent with previous experimental results for the channel geometry considered. The onset of drag reduction occurs at a critical Reynolds number where the viscous sublayer thickness approaches the scale of the superhydrophobic microfeatures and performance is seen to increase with further reduction in viscous sublayer height. These results indicate superhydrophobic surfaces may provide a significant drag reducing mechanism for marine vessels.

  9. Characterization of aerodynamic drag force on single particles: Final report

    Energy Technology Data Exchange (ETDEWEB)

    Kale, S.R.

    1987-10-01

    An electrodynamic balance was used to measure the drag coefficient and also to record the size and shape of spheres, and coal and oil shale particles (100 ..mu..m to 200 ..mu..m in size). The electrodynamic balance consisted of a central, and two end electrodes. The resulting electric field stably suspended a charged particle. A suspended particle, back illuminated by a light emitting diode, was viewed by a video camera. The image was analyzed for particle position control and was calibrated to give the diameter of spheres, or the area equivalent diameter of nonspherical particles. The drag coefficient was calculated from the air velocity and the dc voltage required to keep the particle at the balance center. The particle Reynolds number varied from 0.2 to 13. Three particles each of coal and oil shale were captured and photographed by a scanning electron microscope and the motion of all the particles was recorded on video tape. Drag coefficient vs Reynolds number data for spheres agreed well with correlations. Data for thirteen particles each of coal and oil shale indicated a power law relationship between drag coefficient and Reynolds number. All these particles exhibited higher drag than spheres and were also observed to rotate. The rotation, however, did not affect the drag coefficient. The choice of characteristic dimension affects the drag characteristics of oil shale more strongly than for coal, owing to the flake-like shape of oil shale. 38 figs., 5 tabs.

  10. On the Improvement of Numerical Weather Prediction by Assimilation of Hub Height Wind Information in Convection-Resulted Models

    Science.gov (United States)

    Declair, Stefan; Stephan, Klaus; Potthast, Roland

    2015-04-01

    Determining the amount of weather dependent renewable energy is a demanding task for transmission system operators (TSOs). In the project EWeLiNE funded by the German government, the German Weather Service and the Fraunhofer Institute on Wind Energy and Energy System Technology strongly support the TSOs by developing innovative weather- and power forecasting models and tools for grid integration of weather dependent renewable energy. The key in the energy prediction process chain is the numerical weather prediction (NWP) system. With focus on wind energy, we face the model errors in the planetary boundary layer, which is characterized by strong spatial and temporal fluctuations in wind speed, to improve the basis of the weather dependent renewable energy prediction. Model data can be corrected by postprocessing techniques such as model output statistics and calibration using historical observational data. On the other hand, latest observations can be used in a preprocessing technique called data assimilation (DA). In DA, the model output from a previous time step is combined such with observational data, that the new model data for model integration initialization (analysis) fits best to the latest model data and the observational data as well. Therefore, model errors can be already reduced before the model integration. In this contribution, the results of an impact study are presented. A so-called OSSE (Observation Simulation System Experiment) is performed using the convective-resoluted COSMO-DE model of the German Weather Service and a 4D-DA technique, a Newtonian relaxation method also called nudging. Starting from a nature run (treated as the truth), conventional observations and artificial wind observations at hub height are generated. In a control run, the basic model setup of the nature run is slightly perturbed to drag the model away from the beforehand generated truth and a free forecast is computed based on the analysis using only conventional

  11. 合成气中枢%Syngas Hub

    Institute of Scientific and Technical Information of China (English)

    徐恒泳; 葛庆杰; 李文钊

    2011-01-01

    回顾了人类使用化石能源所经历的煤(固体)、石油(液体)和天然气(气体)燃料的3个时期.针对近年来环境安全和能源清洁化日益重要,而化石能源仍占世界能源主要消费结构的现状,提出了“合成气中枢”的新概念.重点介绍了从天然气、煤和生物质等多种原料气化生产合成气并进行组成调变;煤基和天然气基合成气制化学品的差别;合成气的转化利用,特别是在发电和热-电-化学品多联产、制取清洁燃料和烯烃以及制取代用天然气等方面的研究进展并进行了评述.认为合成气中枢将成为连接石油炼制、石油化工、天然气化工和煤化工以及电力行业的桥梁,有利于资源和能量的最佳利用以及CO2减排.%The consumption history of fossil energy sources including coal ( solid), petroleum (liquid) and natural gas (gas) was briefly reviewed. Although the seeking for non-fossil energy sources is becoming urgent due to the more and more serious global warming, the fossil energy sources will still occupy more than 50% of the global energy consumption before 2050. Therefore, the concept of syngas hub was brought forward, and the following aspects were emphasized in this review: syngas production and its composition adjustment, the difference of syngas to chemicals from coal and natural gas, and syngas conversion and utilization. It was thought that the syngas hub will become a bridge which connects petroleum refining, petrochemical industry, natural gas chemical industry, coal chemical industry and electric power industry, and is further beneficial to the low CO2 emission and the optimal utilization of resources and energy sources.

  12. On the Popularity of GitHub Applications: A Preliminary Note

    OpenAIRE

    Borges, Hudson; Valente, Marco Tulio; Hora, Andre; Coelho, Jailton

    2015-01-01

    GitHub is the world's largest collection of open source software. Therefore, it is important both to software developers and users to compare and track the popularity of GitHub repositories. In this paper, we propose a framework to assess the popularity of GitHub software, using their number of stars. We also propose a set of popularity growth patterns, which describe the evolution of the number of stars of a system over time. We show that stars tend to correlate with other measures, like for...

  13. Low-drag events in transitional wall-bounded turbulence

    Science.gov (United States)

    Whalley, Richard D.; Park, Jae Sung; Kushwaha, Anubhav; Dennis, David J. C.; Graham, Michael D.; Poole, Robert J.

    2017-03-01

    Intermittency of low-drag pointwise wall shear stress measurements within Newtonian turbulent channel flow at transitional Reynolds numbers (friction Reynolds numbers 70 - 130) is characterized using experiments and simulations. Conditional mean velocity profiles during low-drag events closely approach that of a recently discovered nonlinear traveling wave solution; both profiles are near the so-called maximum drag reduction profile, a general feature of turbulent flow of liquids containing polymer additives (despite the fact that all results presented are for Newtonian fluids only). Similarities between temporal intermittency in small domains and spatiotemporal intermittency in large domains is thereby found.

  14. Does Polishing a Rifle Bore Reduce Bullet Drag?

    Science.gov (United States)

    2012-01-17

    thus lower drag. A Remington 700 5R Mil-Spec chambered in 300 Winchester Magnum was used. The bullets used were a 155.5 grain Berger Fullbore Boat...drag on the bullets. 15. SUBJECT TERMS Ballistic coefficient, aerodynamic drag, rifle bore, bore polishing, Remington 700 5R 16. SECURITY...A Remington 700 5R Mil-Spec chambered in 300 Winchester Magnum was used. The bullets used were a 155.5 grain Berger Fullbore Boat Tail and a 125

  15. The Digital Drag and Drop Pillbox

    Science.gov (United States)

    Granger, Bradi B.; Locke, Susan C.; Bowers, Margaret; Sawyer, Tenita; Shang, Howard; Abernethy, Amy P.; Bloomfield, Richard A.; Gilliss, Catherine L.

    2017-01-01

    Objective: We present the design and feasibility testing for the “Digital Drag and Drop Pillbox” (D-3 Pillbox), a skill-based educational approach that engages patients and providers, measures performance, and generates reports of medication management skills. Methods: A single-cohort convenience sample of patients hospitalized with heart failure was taught pill management skills using a tablet-based D-3 Pillbox. Medication reconciliation was conducted, and aptitude, performance (% completed), accuracy (% correct), and feasibility were measured. Results: The mean age of the sample (n = 25) was 59 (36–89) years, 50% were women, 62% were black, 46% were uninsured, 46% had seventh-grade education or lower, and 31% scored very low for health literacy. However, most reported that the D-3 Pillbox was easy to read (78%), easy to repeat-demonstrate (78%), and comfortable to use (tablet weight) (75%). Accurate medication recognition was achieved by discharge in 98%, but only 25% reported having a “good understanding of my responsibilities.” Conclusions: The D-3 Pillbox is a feasible approach for teaching medication management skills and can be used across clinical settings to reinforce skills and medication list accuracy. PMID:28282304

  16. Turbulent drag reduction through oscillating discs

    CERN Document Server

    Wise, Daniel J

    2014-01-01

    The changes of a turbulent channel flow subjected to oscillations of wall flush-mounted rigid discs are studied by means of direct numerical simulations. The Reynolds number is $R_\\tau$=$180$, based on the friction velocity of the stationary-wall case and the half channel height. The primary effect of the wall forcing is the sustained reduction of wall-shear stress, which reaches a maximum of 20%. A parametric study on the disc diameter, maximum tip velocity, and oscillation period is presented, with the aim to identify the optimal parameters which guarantee maximum drag reduction and maximum net energy saving, computed by taking into account the power spent to actuate the discs. This may be positive and reaches 6%. The Rosenblat viscous pump flow is used to predict the power spent for disc motion in the turbulent channel flow and to estimate localized and transient regions over the disc surface subjected to the turbulent regenerative braking effect, for which the wall turbulence exerts work on the discs. The...

  17. The 'W' prawn-trawl with emphasised drag-force transfer to its centre line to reduce overall system drag.

    Directory of Open Access Journals (Sweden)

    Cheslav Balash

    Full Text Available For prawn trawling systems, drag reduction is a high priority as the trawling process is energy intensive. Large benefits have occurred through the use of multiple-net rigs and thin twine in the netting. An additional positive effect of these successful twine-area reduction strategies is the reduced amount of otter board area required to spread the trawl systems, which leads to further drag reduction. The present work investigated the potential of redirecting the drag-strain within a prawn trawl away from the wings and the otter boards to the centre line of the trawl, where top and bottom tongues have been installed, with an aim to minimise the loading/size of the otter boards required to spread the trawl. In the system containing the new 'W' trawl, the drag redirected to the centre-line tongues is transferred forward through a connected sled and towing wires to the trawler. To establish the extent of drag redirection to the centre-line tongues and the relative drag benefits of the new trawl system, conventional and 'W' trawls of 3.65 m headline length were tested firstly over a range of spread ratios in the flume tank, and subsequently at optimum spread ratio in the field. The developed 'W' trawl effectively directed 64% of netting-drag off the wings and onto the centre tongues, which resulted in drag savings in the field of ∼20% for the associated 'W' trawl/otter-board/sled system compared to the traditional trawl/otter-board arrangement in a single trawl or twin rig configuration. Furthermore, based on previously published data, the new trawl when used in a twin rig system is expected to provide approximately 12% drag reduction compared to quad rig. The twin 'W' trawl system also has benefits over quad rig in that a reduced number of cod-end/By-catch Reduction Device units need to be installed and attended each tow.

  18. Assessing wave energy effects on biodiversity: the wave hub experience.

    Science.gov (United States)

    Witt, M J; Sheehan, E V; Bearhop, S; Broderick, A C; Conley, D C; Cotterell, S P; Crow, E; Grecian, W J; Halsband, C; Hodgson, D J; Hosegood, P; Inger, R; Miller, P I; Sims, D W; Thompson, R C; Vanstaen, K; Votier, S C; Attrill, M J; Godley, B J

    2012-01-28

    Marine renewable energy installations harnessing energy from wind, wave and tidal resources are likely to become a large part of the future energy mix worldwide. The potential to gather energy from waves has recently seen increasing interest, with pilot developments in several nations. Although technology to harness wave energy lags behind that of wind and tidal generation, it has the potential to contribute significantly to energy production. As wave energy technology matures and becomes more widespread, it is likely to result in further transformation of our coastal seas. Such changes are accompanied by uncertainty regarding their impacts on biodiversity. To date, impacts have not been assessed, as wave energy converters have yet to be fully developed. Therefore, there is a pressing need to build a framework of understanding regarding the potential impacts of these technologies, underpinned by methodologies that are transferable and scalable across sites to facilitate formal meta-analysis. We first review the potential positive and negative effects of wave energy generation, and then, with specific reference to our work at the Wave Hub (a wave energy test site in southwest England, UK), we set out the methodological approaches needed to assess possible effects of wave energy on biodiversity. We highlight the need for national and international research clusters to accelerate the implementation of wave energy, within a coherent understanding of potential effects-both positive and negative.

  19. Proof test of hybrid shrink fits with ceramic hub

    Science.gov (United States)

    Wagner, M.; Binz, H.

    2011-10-01

    Advanced ceramic machine components are required in many applications because of their specific material properties like high hardness, resistance to chemicals, corrosion and wear, low specific weight etc. The most suitable shaft-hub connection to ceramics is an interference fit assembly because it is free of geometrical notches and transmission of forces takes place in a large area. Such a shrink fit is rated for endurance strength when the stress intensity factor is below the specific value KI0 where no crack growth occurs. The total component suddenly fails, when the stress intensity factor exceeds the KIC value. The load to the press fit during the joining process, caused by the interference of the assembly, could be regulated by ambient conditions. In case of undetected material defects or microcracks in the ceramic and if the stress intensity is below KIC, the ceramic will not fail but a crack could grow. Thus, the joining process only seems to be a proof test. When the load during operation leads to a stress intensity that remains higher than KI0 the crack grows until the whole ceramic component fails. This effect was verified in tests at the Institute for Engineering Design and Industrial Design.

  20. Proof test of hybrid shrink fits with ceramic hub

    Energy Technology Data Exchange (ETDEWEB)

    Wagner, M; Binz, H, E-mail: markus.wagner@iktd.uni-stuttgart.de [Institute for Engineering Design and Industrial Design, University of Stuttgart (Germany)

    2011-10-29

    Advanced ceramic machine components are required in many applications because of their specific material properties like high hardness, resistance to chemicals, corrosion and wear, low specific weight etc. The most suitable shaft-hub connection to ceramics is an interference fit assembly because it is free of geometrical notches and transmission of forces takes place in a large area. Such a shrink fit is rated for endurance strength when the stress intensity factor is below the specific value K{sub I0} where no crack growth occurs. The total component suddenly fails, when the stress intensity factor exceeds the K{sub IC} value. The load to the press fit during the joining process, caused by the interference of the assembly, could be regulated by ambient conditions. In case of undetected material defects or microcracks in the ceramic and if the stress intensity is below K{sub IC}, the ceramic will not fail but a crack could grow. Thus, the joining process only seems to be a proof test. When the load during operation leads to a stress intensity that remains higher than K{sub I0} the crack grows until the whole ceramic component fails. This effect was verified in tests at the Institute for Engineering Design and Industrial Design.

  1. Nuclear isoscaling and fair sampling

    Science.gov (United States)

    Lopez, Jorge

    2008-10-01

    The isoscaling phenomenon was first observed in nuclear multifragmentation experiments and has become a hot topic as it could provide a probe of the nuclear equation of state to understand nuclear matter at extreme condition of isospin such as in neutron stars. The present work studies isoscaling using 1) classical molecular dynamics simulations, 2) percolation and 3) probabilistic arguments, and determines that isoscaling is a general phenomenon that can exist independent of the nuclear reaction, and it is expected to occur in disassemblying systems with no more than fair sampling. In collaboration with Alan Davila, University of Texas at Austin; Claudio Dorso, Universidad de Buenos Aires; Carlos Hernandez, Universidad de Colima; Christian Escudero, University of Texas at El Paso; and Jorge Muñoz, CalTech.

  2. The PANDA experiment at FAIR

    Energy Technology Data Exchange (ETDEWEB)

    Destefanis, M.

    2013-12-15

    The PANDA (antiProton ANnihilation at DArmstadt) experiment is one of the major projects in preparation at the upcoming FAIR facility in Darmstadt, Germany. It will study interactions between antiprotons and protons or nuclei in the momentum range from 1.5 GeV/c to 15 GeV/c. The PANDA scientific program will address a wide range of topics, all aiming at improving our understanding of the strong interaction and hadron structure. The PANDA detector is a general-purpose spectrometer that will collect high quality and high statistics data in the fields of meson spectroscopy, baryon-antibaryon production, baryon spectroscopy, hypernuclear physics, hadron properties in the nuclear medium, and nucleon structure. This paper reviews some of the main physics topics of the experiment, together with a presentation of the detector.

  3. Modelagem para localização de hubs no transporte de encomendas expressas Modelling for location hubs in the express cargo transport

    Directory of Open Access Journals (Sweden)

    Javier Antonio Timaná Alamo

    2006-12-01

    Full Text Available Na presente pesquisa se propõe um modelo matemático de programação linear com variáveis binárias 0/1, para projetar a configuração de uma rede de distribuição de encomendas expressas, visando minimizar os custos e garantindo um bom nível de serviço. O modelo, que é uma modificação da formulação proposta por O’Kelly, define as posições dos hubs, a alocação deles às demais instalações físicas e a construção de roteiros com apenas uma parada intermediária, o que confere mais agilidade ao atendimento da demanda de transporte de carga. Considera-se a instalação de um único hub maior (Hub Principal, que serve como ponto de transbordo para os fluxos de carga entre as distintas regiões de um território, e um conjunto de terminais regionais (mini-hubs, servindo como ponto de conexão, unicamente, para os fluxos de carga existentes em um determinado raio de cobertura. Foram propostas extensões que incluem uma restrição da capacidade operacional do Hub Principal, para evitar seu congestionamento, e duas diferentes estratégias de induzir o aumento de fluxo de carga manipulado pelos mini-hubs. O modelo proposto e suas extensões foram aplicados ao estudo de um caso real, obtendo-se resultados consistentes e uma redução significativa no custo total da rede de distribuição da empresa analisada.This study proposes a mathematical model of linear programming with binary variables 0/1 to project the configuration of a distribution network for express cargo which aims to minimize costs and guarantee a high level of service. The model, which is a modification of the formulation proposed by O’Kelly, defines the position of the hubs, their allocation regarding the other physical installations, and the building of itineraries with only one intermediate stop, which increases agility in meeting the demand of cargo transport. It assumes the installation of a single, major hub (Main Hub, which serves as the transfer point for

  4. Constructing Invariant Fairness Measures for Surfaces

    DEFF Research Database (Denmark)

    Gravesen, Jens; Ungstrup, Michael

    1998-01-01

    This paper presents a general method which from an invariant curve fairness measure constructs an invariant surface fairness measure. Besides the curve fairness measure one only needs a class of curves on the surface for which one wants to apply the curve measure. The surface measure at a point...... variation.The method is extended to the case where one considers, not the fairness of one curve, but the fairness of a one parameter family of curves. Such a family is generated by the flow of a vector field, orthogonal to the curves. The first, respectively the second order derivative along the curve...... of the size of this vector field is used as the fairness measure on the family.Six basic 3rd order invariants satisfying two quadratic equations are defined. They form a complete set in the sense that any invariant 3rd order function can be written as a function of the six basic invariants together...

  5. The ontogeny of fairness in seven societies.

    Science.gov (United States)

    Blake, P R; McAuliffe, K; Corbit, J; Callaghan, T C; Barry, O; Bowie, A; Kleutsch, L; Kramer, K L; Ross, E; Vongsachang, H; Wrangham, R; Warneken, F

    2015-12-10

    A sense of fairness plays a critical role in supporting human cooperation. Adult norms of fair resource sharing vary widely across societies, suggesting that culture shapes the acquisition of fairness behaviour during childhood. Here we examine how fairness behaviour develops in children from seven diverse societies, testing children from 4 to 15 years of age (n = 866 pairs) in a standardized resource decision task. We measured two key aspects of fairness decisions: disadvantageous inequity aversion (peer receives more than self) and advantageous inequity aversion (self receives more than a peer). We show that disadvantageous inequity aversion emerged across all populations by middle childhood. By contrast, advantageous inequity aversion was more variable, emerging in three populations and only later in development. We discuss these findings in relation to questions about the universality and cultural specificity of human fairness.

  6. Constructing Invariant Fairness Measures for Surfaces

    DEFF Research Database (Denmark)

    Gravesen, Jens; Ungstrup, Michael

    1998-01-01

    This paper presents a general method which from an invariant curve fairness measure constructs an invariant surface fairness measure. Besides the curve fairness measure one only needs a class of curves on the surface for which one wants to apply the curve measure. The surface measure at a point...... variation.The method is extended to the case where one considers, not the fairness of one curve, but the fairness of a one parameter family of curves. Such a family is generated by the flow of a vector field, orthogonal to the curves. The first, respectively the second order derivative along the curve...... of the size of this vector field is used as the fairness measure on the family.Six basic 3rd order invariants satisfying two quadratic equations are defined. They form a complete set in the sense that any invariant 3rd order function can be written as a function of the six basic invariants together...

  7. Towards a Fair Global Economic Regime?

    DEFF Research Database (Denmark)

    Staricco, Juan Ignacio

    This dissertation offers an assessment of Fair Trade’s transformative potential through an empirical examination of the case of Fair Trade wine produced in Argentina and consumed in the United Kingdom. Guided by a dialectical understanding of the research process, the analysis is done at various...... levels of generality, offering both case-specific and universal arguments about the Fair Trade system as a whole. Theoretically, the dissertation develops a regulationist framework based on a critical engagement with the French Regulation Approach and the Amsterdam Project in International Political....... The further exploration of Fair Trade’s political and ideological dimensions sheds light on the reasons behind the system’s current limitations. The analysis shows that Fair Trade offers very limited improvements compared to the conventional economy. Additionally, for the Argentinean wine industry, Fair Trade...

  8. Not All Fun at the Fair

    Institute of Scientific and Technical Information of China (English)

    HU YUE

    2011-01-01

    As growing uncertainties hang over China's trade front,a closer look at the latest Canton Fair,a barometer of China's foreign trade,can provide an insight on how exporters are faring.Officially known as the China Import and Export Fair,the biannual Canton Fair is held every spring and autumn in Guangzhou,capital of south Chian's Guangdong Province,and each fair has three phases.The 110th Canton Fair,held from October 15 to November 4,attracted more than 24,000 enterprises from home and abroad.Its first two phases witnessed export deals worth around $33.18billion,up 3.2 percent over the spring fair.

  9. Fair Scheduling in Networks Through Packet Election

    CERN Document Server

    Jagabathula, Srikanth

    2008-01-01

    We consider the problem of designing a fair scheduling algorithm for discrete-time constrained queuing networks. Each queue has dedicated exogenous packet arrivals. There are constraints on which queues can be served simultaneously. This model effectively describes important special instances like network switches, interference in wireless networks, bandwidth sharing for congestion control and traffic scheduling in road roundabouts. Fair scheduling is required because it provides isolation to different traffic flows; isolation makes the system more robust and enables providing quality of service. Existing work on fairness for constrained networks concentrates on flow based fairness. As a main result, we describe a notion of packet based fairness by establishing an analogy with the ranked election problem: packets are voters, schedules are candidates and each packet ranks the schedules based on its priorities. We then obtain a scheduling algorithm that achieves the described notion of fairness by drawing upon ...

  10. Electromagnetically-Induced Frame-Dragging around Astrophysical Objects

    CERN Document Server

    Ruiz, Andrés F Gutiérrez

    2015-01-01

    Frame dragging (Lense-Thirring effect) is generally associated with rotating astrophysical objects. However, it can also be generated by electromagnetic fields if electric and magnetic fields are simultaneously present. In most models of astrophysical objects, macroscopic charge neutrality is assumed and the entire electromagnetic field is characterized in terms of a magnetic dipole component. Hence, the purely electromagnetic contribution to the frame dragging vanishes. However, strange stars may posses independent electric dipole and neutron stars independent electric quadrupole moments that may lead to the presence of purely electromagnetic contributions to the frame dragging. Moreover, recent observations have shown that in stars with strong electromagnetic fields, the magnetic quadrupole may have a significant contribution to the dynamics of stellar processes. As an attempt to characterized and quantify the effect of electromagnetic frame-dragging in this kind of astrophysical objects, an analytic soluti...

  11. Rotating cylinder drag balance with application to riblets

    Science.gov (United States)

    Hall, T.; Joseph, D.

    2000-12-01

    Experimental results are reported and discussed for a rotating cylinder drag balance designed to predict drag reduction by surfaces like riblets. The apparatus functions by measuring the torque applied to the inner cylinder by a fluid, such as water, that is set in motion by the controlled rotation of the outer cylinder. The instrument was validated by calibration for laminar flow and comparison of turbulent flow results to the those of G. I. Taylor. The ability to predict drag reduction was demonstrated by testing 114 m symmetric sawtooth riblets, which gave a maximum reduction of about 5% and an overall drag reduction range of 5

  12. Jet Lag a Drag on Pro Baseball Players

    Science.gov (United States)

    ... 163187.html Jet Lag a Drag on Pro Baseball Players Study found traveling across time zones linked ... might be more than just tiring for pro baseball players: The resulting jet lag may actually harm ...

  13. Constraining the Drag Coefficients of Meteors in Dark Flight

    Science.gov (United States)

    Carter, R. T.; Jandir, P. S.; Kress, M. E.

    2011-01-01

    Based on data in the aeronautics literature, we have derived functions for the drag coefficients of spheres and cubes as a function of Mach number. Experiments have shown that spheres and cubes exhibit an abrupt factor-of-two decrease in the drag coefficient as the object slows through the transonic regime. Irregularly shaped objects such as meteorites likely exhibit a similar trend. These functions are implemented in an otherwise simple projectile motion model, which is applicable to the non-ablative dark flight of meteors (speeds less than .+3 km/s). We demonstrate how these functions may be used as upper and lower limits on the drag coefficient of meteors whose shape is unknown. A Mach-dependent drag coefficient is potentially important in other planetary and astrophysical situations, for instance, in the core accretion scenario for giant planet formation.

  14. Experimental study of drag reduction in flumes and spillway tunnels

    Institute of Scientific and Technical Information of China (English)

    Ying-kui WANG; Chun-bo JIANG

    2010-01-01

    Experiments in an open flume model and spillway tunnel model were carried out using drag reduction techniques.Two drag reduction techniques were adopted in the experiments:polymer addition and coating.The drag reduction effect of a polyacrylamide(PAM)solution and dimethyl silicone oil coating were studied in the flume model experiments,and the results were analyzed.Experiments were then carried out with a model of the Xiluodu Hydropower Station,the second largest dam in China.In order to reduce the resistance,the spillway tunnels were internally coated with dimethyl silicone oil.This is the first time that these drag reduction techniques have been applied to so large a hydraulic model.The experimental results show that the coating technique can effectively increase flood discharge.The outlet velocity and the jet trajectory distance are also increased,which enhances the energy dissipation of the spillway tunnel.

  15. Shell selection of hermit crabs is influenced by fluid drag

    Science.gov (United States)

    Casillas, Barbara; Ledesma, Rene; Alcaraz, Guillermina; Zenit, Roberto

    2010-11-01

    The flow around gastropod shells used by hermit crabs (Calcinus californiensis) was visualized experimentally. These crabs choose their shells according to many factors; we found that the choice of shell (shape and weight) is directly related to the drag caused over them by the exposure to wave action. Tests were conducted in a wind tunnel to investigate flow differences for shells of various shapes. A particle image velocimetry (PIV) system was used to visualize the flow field. The images above show the flow field around two types of shells (Thais speciosa and Nerita scabircosta) for Reynolds numbers of O(10^5). Using a control volume analysis, the drag coefficient was inferred. Several shell geometries, orientations and mean flow velocities were tested. In this talk, the flow and drag force will be shown for the different arrangements. A discussion of the relation between drag and shape will be presented.

  16. Development of Drag Reducing Polymer of FDR-SPC

    Science.gov (United States)

    Lee, Inwon; Park, Hyun; Chun, Ho Hwan

    2015-11-01

    In this study, a novel FDR-SPC (Frictional Drag Reduction Self-Polishing Copolymer) is first synthesized in this study. The drag reducing functional radical such as PEGMA (Poly(ethylene) glycol methacrylate) has been utilized to participate in the synthesis process of the SPC. The release mechanism of drag reducing radical is accounted for the hydrolysis reaction between the FDR-SPC and seawater. The types of the baseline SPC monomers, the molecular weight and the mole fraction of PEGMA were varied in the synthesis process. The resulting SPCs were coated to the substrate plates for the subsequent hydrodynamic test for skin friction measurement. A significant reduction in Reynolds stress was observed in a range of specimen, with the maximum drag reduction being 15.9% relative to the smooth surface for PRD3-1.

  17. Collecting responses through Web page drag and drop.

    Science.gov (United States)

    Britt, M Anne; Gabrys, Gareth

    2004-02-01

    This article describes how to collect responses from experimental participants using drag and drop on a Web page. In particular, we describe how drag and drop can be used in a text search task in which participants read a text and then locate and categorize certain elements of the text (e.g., to identify the main claim of a persuasive paragraph). Using this technique, participants respond by clicking on a text segment and dragging it to a screen field or icon. We have successfully used this technique in both the argument element identification experiment that we describe here and a tutoring system that we created to teach students to identify source characteristics while reading historical texts (Britt, Perfetti, Van Dyke, & Gabrys, 2000). The implementation described here exploits the capability of recent versions of Microsoft's Internet Explorer Web browser to handle embedded XML documents and drag and drop events.

  18. Separability of drag and thrust in undulatory animals and machines

    National Research Council Canada - National Science Library

    Bale, Rahul; Shirgaonkar, Anup A; Neveln, Izaak D; Bhalla, Amneet Pal Singh; MacIver, Malcolm A; Patankar, Neelesh A

    2014-01-01

    .... Prior approaches have failed to provide a separation of these two forces for undulatory swimmers such as lamprey and eels, where most parts of the body are simultaneously generating drag and thrust...

  19. Sugar and Alcoholic Fair Closed in Chengdu

    Institute of Scientific and Technical Information of China (English)

    Li Zhen

    2009-01-01

    @@ The 80th China National Sugar and Alcoholic Commodities Fair was held in Chengdu (capital of Sichuan province) from March 24 to 28.Sponsored by China National Sugar and Alcohol Group Corp.,this is the 20th time for Chengdu to host such a big event.Since the fair was initially held in 1955,Sugar and Alcoholic Fair has become increasingly well-known in both China and abroad while sticking to the principle of serving enterprises.

  20. Health fairs bring wellness concepts to life.

    Science.gov (United States)

    Serina, M; Giove, S

    1991-01-01

    Incorporated into the nursing curriculum, the health fair is a stimulating, unique, nontraditional educational project that examines effective health education tools, leadership skills, and interaction with the community. Students test theories and collaborate with other school disciplines while planning, implementing, and evaluating health education and health fair promotion. Health fairs help students to identify positive lifestyles and create opportunities to test the skills needed to improve the population's wellness level.

  1. The hub wall boundary layer development and losses in an axial flow compressor rotor passage

    Science.gov (United States)

    Murthy, K. N. S.; Lakshminarayana, B.

    1987-02-01

    The hub wall boundary layer development in a compressor stage including the rotor passage is experimentally investigated. A miniature five-hole probe was employed to measure the hub wall boundary layer inside the inlet guide vane passage, upstream and far downstream of the rotor. The hub wall boundary layer inside the rotor passage was acquired using a rotating miniature five-hole probe. The boundary layer is well behaved upstream and far downstream of the rotor. The migration of the hub wall boundary layer towards the suction surface corner is observed. The limiting streamline angles and static pressure distribution across the stage were also measured. The mean velocity profiles and the integral properties upstream, inside and downstream of the rotor, and the losses are presented and interpreted.

  2. Numerical and Experimental Investigation of Heat Flow in Permanent Magnet Brushless DC Hub Motor

    DEFF Research Database (Denmark)

    Fasil, Muhammed; Plesner, Daniel; Walther, Jens Honore

    2014-01-01

    in the stator. The hub motor construction restricts the available conductive paths for heat dissipation from the stator to the ambient only through the shaft. In contrast to an internal rotor structure, where the stator winding losses are diffused via conduction, here convection plays a major role in loss...... dissipation. Therefore, a LP thermal model with improved convection modelling has been proposed to calculate the temperature of the components inside the hub motor. The developed model is validated with the FE thermal model and the test data. In addition, CFD tools has been used to accurately model...... the internal and the external flow as well as the convective heat transfer of the hub motor. Finally, an optimization study of the hub motor has been carried out using the CFD model to improve heat transfer from the stator....

  3. Collaborative Policy of the Supply-Hub for Assemble-to-Order Systems with Delivery Uncertainty

    Directory of Open Access Journals (Sweden)

    Guo Li

    2014-01-01

    Full Text Available This paper considers the collaborative mechanisms of the Supply-Hub in the Assemble-to-Order system (ATO system hereafter with upstream delivery uncertainty. We first propose a collaborative replenishment mechanism in the ATO system, and construct a replenishment model with delivery uncertainty in use of the Supply-Hub. After transforming the original model into a one-dimensional optimization problem, we derive the optimal assembly quantity and reorder point of each component. In order to enable the Supply-Hub to conduct collaborative replenishment with each supplier, the punishment and reward mechanisms are proposed. The numerical analysis illustrates that service level of the Supply-Hub is an increasing function of both punishment and reward factors. Therefore, by adjusting the two factors, suppliers’ incentives of collaborative replenishment can be significantly enhanced, and then the service level of whole ATO system can be improved.

  4. Puertos, espacio y globalización: el desarrollo de hubs en México

    Directory of Open Access Journals (Sweden)

    Carlos Daniel Martner Peyrelongue

    2010-01-01

    Full Text Available Los puertos hubs se presentan como el nuevo paradigma de desarrollo del transporte y el comercio marítimo internacional en la globalización. Prácticamente todos los países latinoamericanos anuncian megaproyectos para el desarrollo de puertos hubs en sus litorales, generando grandes expectativas de desarrollo regional, con un débil sustento tanto teórico como empírico. En este sentido, el presente trabajo busca contribuir a la caracterización del modelo de puertos hubs en países periféricos dentro de la economíamundo capitalista, aludiendo, en especial, al caso mexicano. Se trata de aportar elementos de análisis para reconocer, a grandes rasgos, las posibilidades del desarrollo de hubs en los litorales mexicanos, desde la perspectiva de los estudios regionales y la geografía del transporte.

  5. Empirical analysis on the human dynamics of blogging behavior on GitHub

    Science.gov (United States)

    Yan, Deng-Cheng; Wei, Zong-Wen; Han, Xiao-Pu; Wang, Bing-Hong

    2017-01-01

    GitHub is a social collaborative coding platform on which software developers not only collaborate on codes but also share knowledge through blogs using GitHub Pages. In this article, we analyze the blogging behavior of software developers on GitHub Pages. The results show that both the commit number and the inter-event time of two consecutive blogging actions follow heavy-tailed distribution. We further observe a significant variety of activity among individual developers, and a strongly positive correlation between the activity and the power-law exponent of the inter-event time distribution. We also find a difference between the user behaviors of GitHub Pages and other online systems which is driven by the diversity of users and length of contents. In addition, our result shows an obvious difference between the majority of developers and elite developers in their burstiness property.

  6. Sci-Hub: What Librarians Should Know and Do about Article Piracy.

    Science.gov (United States)

    Hoy, Matthew B

    2017-01-01

    The high cost of journal articles has driven many researchers to turn to a new way of getting access: "pirate" article sites. Sci-Hub, the largest and best known of these sites, currently offers instant access to more than 58 million journal articles. Users attracted by the ease of use and breadth of the collection may not realize that these articles are often obtained using stolen credentials and downloading them may be illegal. This article will briefly describe Sci-Hub and how it works, the legal and ethical issues it raises, and the problems it may cause for librarians. Librarians should be aware of Sci-Hub and the ways it may change their patrons' expectations. They should also understand the risks Sci-Hub can pose to their patrons and their institutions.

  7. Imitation and Innovation in Fashion: Mapping the Creative Process in "Modinha" Segment on a Regional Fair

    Directory of Open Access Journals (Sweden)

    Thalita Silva Calíope

    2016-06-01

    Full Text Available Fashion is recognized by transience, resulting in its short life cycle, since the constant changes make what was previously considered "fashionable" obsolete (Emidio & Sabione, 2010. In this market, innovate and act before competitors, accelerate the launch of products, reduce design time and the placement of new items on the market is a survival condition (Lipovetsky, 2007. A central factor in the fashion spread is imitation, as this promotes both innovation and obsolescence, forcing producers to set up periodically (Caulkins et al., 2007, Pesendorfer, 1995. The research object is the "modinha", women's clothing that follows media trends, is the copying, with or without changes, to the mass market (Avelar, 2009; Victor, 2007, in this study, "José Avelino Street Fair". This fair meets weekly hundreds of manufacturers in a metropolis of northeastern Brazil that has been established as a fashion hub. Thus, it was proposed to identify the process of innovation in companies that make “modinha” in this Fair. The research was conducted through a survey and data were obtained from a questionnaire administered with 78 stallholders. One descriptive and exploratory data analysis was performed. It was found that, contrary to expectation, a considerable formality, with 49 of the 78 respondents with CNPJ; its customers are small retailers; and their competitors are the stallholders. Regarding the creation of clothes models, the stallholders research in various sources and said imitating models from these sources, but they try to make changes.

  8. Drag force in a charged N = 4 SYM plasma

    Energy Technology Data Exchange (ETDEWEB)

    Caceres, Elena [Facultad de Ciencias, Universidad de Colima, Bernal Diaz del Castillo 340, Colima (Mexico); Gueijosa, Alberto [Departamento de Fisica de Altas Energias, Instituto de Ciencias Nucleares, Universidad Autonoma de Mexico, Apdo. Postal 70-543, D.F. 04510 (Mexico)

    2006-11-15

    Following recent developments, we employ the AdS/CFT correspondence to determine the drag force exerted on an external quark that moves through an N = 4 super-Yang-Mills plasma with a non-zero R-charge density (or, equivalently, a non-zero chemical potential). We find that the drag force is larger than in the case where the plasma is neutral, but the dependence on the charge is non-monotonic.

  9. Separability of drag and thrust in undulatory animals and machines

    OpenAIRE

    Bale, R; Shirgaonkar, AA; Neveln, ID; Bhalla, APS; MacIver, MA; Patankar, NA

    2014-01-01

    For nearly a century, researchers have tried to understand the swimming of aquatic animals in terms of a balance between the forward thrust from swimming movements and drag on the body. Prior approaches have failed to provide a separation of these two forces for undulatory swimmers such as lamprey and eels, where most parts of the body are simultaneously generating drag and thrust. We nonetheless show that this separation is possible, and delineate its fundamental basis in undulatory swimmers...

  10. ON THE AUDIT OF FAIR VALUE MEASUREMENTS

    National Research Council Canada - National Science Library

    Jatinder P Singh; Prince Doliya

    2015-01-01

      In this article, the hypotheses on whether the auditor's functional domain, approach, methodology and responsibilities are undergoing a metamorphosis with the adoption of Fair Value Accounting (FVA...

  11. A GENERALIZED VERSION OF PLAY FAIR CIPHER

    Directory of Open Access Journals (Sweden)

    Jitendra Choudhary

    2013-06-01

    Full Text Available In this paper, we have generalized and modified the play fair cipher. We have introduced confusion and diffusion. The cryptanalysis carried out in this analysis has shown that the proposed play fair cipher is a strong one. The role of cryptography in today’s world is increasing day by day. Information is flowing from are place to another on the network. One most common cryptography technique is substitution cipher. Play fair is most common substitution cipher. In this paper, we present a generalized version of play fair ciphers. Encryption/decryption is a very popular task. We also explain the fundamentals of sequential cryptography.

  12. Fair at the Temple of Earth

    Institute of Scientific and Technical Information of China (English)

    1998-01-01

    WITH all of its fun and games, the Spring Festival fair at the Temple of Earth in Beijing is a good place to spend the holidays. Ever since 1985, when the temple first resumed the practice of holding the fair during the Spring Festival, the annual event has attracted more and more people every year. In fact, the temple fair has gradually developed into a holiday exhibition of traditional local culture as well as an influential mass cultural activity. The opening ceremony is a major part of the temple fair. All who attend are impressed by its magnificence and liveliness. The arch tower at the entrance

  13. Fair division theory and climate change policy

    Energy Technology Data Exchange (ETDEWEB)

    Helm, C. [Technical University Darmstadt (Germany). Department of Law and Economics

    2008-09-30

    This paper analyzes the fair division of common property resources when monetary compensations are feasible. A prominent example is the fair division of the atmosphere's limited absorptive capacity for greenhouse gases. I propose a solution that is Pareto efficient and satisfies the axiomatic fair division criteria of individual rationality, stand-alone upper bound, and a version of envy-freeness. The latter criterion is adapted to problems where monetary compensations can be used to facilitate the fair division of the common resource. Applied to climate change, the solution implies that developing countries should participate in emission reduction efforts, but should be fully compensated for their incremental abatement costs.

  14. Canton Fair: Warm in the Cold Weather

    Institute of Scientific and Technical Information of China (English)

    Wang Ting

    2009-01-01

    @@ Number of Buyers A modest rise was seen in the number of overseas buyers attending the fair. According to the statistics, in this session, the number of overseas buyers from 212 countries and regions was 188170, 22734 more than that of the spring session representing an increase of 13.7%, and 13608 more than that of last Autumn Fair in 2008, representing an increase of 7.8%. Buyers from EU and USA resumed their attendance to the Fair significantly and new buyers attending the Fair have increased.

  15. Summer Fair in the Ice City

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The 19th International China Harbin Fair for Trade and Economic Cooperation reaped a lot in terms of China-foreign trade contracts Harbin, the provincial capital of northeast China’s Heilongjiang Province, has long been well known to the world for its cold cli- mate, and especially for its annual ice festival in December. But each summer from June 15 to 19, the city has another mission: to hold an international trade fair-the International China Harbin Fair for Trade and Economic Cooperation (Harbin Trade Fair).

  16. FAIR PLAY I N TURKISH SOCIAL LIFE

    Directory of Open Access Journals (Sweden)

    Mikail TEL

    2014-07-01

    Full Text Available We can say that we start hearing term of fair play since last 30 years in our country. While it is a sportive term it also represents respectfulness toward all mutual rights, symbol of being just and honest also we can determine it as basic moral values wh ich needs to be practise. Expression and teaching of Fair play fact starts with family and it needs to be thought as a life discipline which should appear in society. Term of Fair play isn‟t only an organizing term for sportive interrelations it also ne eds to be taken as a cultural fact. It is a way of life. Term of Fair play is a way of thinking and acting so it is is above all of sport branches. It is behaviors and emotions which are accepted as conditions of being a perfect human being by Turkish society. Purpose of this study is to investigate perspective of Turkish society toward Fair play and find lived / real fair play events to set as sample. Term of Fair play, cultural values among Turkish society and real Fair play events had been studied carefully within the theorical scope. This research is a theorical study. Screening the resources used as method for this study. Tried to investigate works, articles and researches had been done about this field and interpret the facts which can be acc epted as sample for Fair play.

  17. A Dynamic Calibration Method for Experimental and Analytical Hub Load Comparison

    Science.gov (United States)

    2017-03-01

    ARL-RP-0592 ● Mar 2017 US Army Research Laboratory A Dynamic Calibration Method for Experimental and Analytical Hub Load Comparison by Robert P... A Dynamic Calibration Method for Experimental and Analytical Hub Load Comparison by Robert P Thornburgh, Andrew R Kreshock, and Matthew L...other provision of law, no person shall be subject to any penalty for failing to comply with a collection of information if it does not display a

  18. TURBULENCE TRANSPORT OF SURFACTANT SOLUTION FLOW DURING DRAG REDUCTION DEGENERATION

    Institute of Scientific and Technical Information of China (English)

    GU Wei-guo; WANG De-zhong

    2012-01-01

    Turbulence transport of surfactant solution flow during drag reduction degeneration is investigated experimentally in a two-dimensional channel.Particle Image Velocimetry (P1V) system is used to take two-dimensional velocity frames in the streamwise and wall-normal plane.The additive of surfactant is cetyltrimethyl ammonium chloride (CTAC) with the mass concentration of 25 ppm.Drag reduction degeneration happens in the CTAC solution flow,exhibiting the maximal drag reduction at Re =25000and losing drag reduction completely at Re =40 000.The velocity frames are statistically analyzed in four quadrants which are divided by the u -axis and v-axis.It is found that the phenomenon of“Zero Reynolds shear stress” is caused by the decrease of wallnormal fluctuations and its symmetrical distribution in quadrants.The increase of Reynolds number leads to the enhancement of turbulence burst phenomenon.During thc drag reduction degeneration,the CTAC solution flow contains both high turbulence intensity and drag reduction states.

  19. CME propagation: Where does the solar wind drag take over?

    CERN Document Server

    Sachdeva, Nishtha; Colaninno, Robin; Vourlidas, Angelos

    2015-01-01

    We investigate the Sun-Earth dynamics of a set of eight well observed solar coronal mass ejections (CMEs) using data from the STEREO spacecraft. We seek to quantify the extent to which momentum coupling between these CMEs and the ambient solar wind (i.e., the aerodynamic drag) influences their dynamics. To this end, we use results from a 3D flux rope model fit to the CME data. We find that solar wind aerodynamic drag adequately accounts for the dynamics of the fastest CME in our sample. For the relatively slower CMEs, we find that drag-based models initiated below heliocentric distances ranging from 15 to 50 $R_{\\odot}$ cannot account for the observed CME trajectories. This is at variance with the general perception that the dynamics of slow CMEs are influenced primarily by solar wind drag from a few $R_{\\odot}$ onwards. Several slow CMEs propagate at roughly constant speeds above 15--50 $R_{\\odot}$. Drag-based models initiated above these heights therefore require negligible aerodynamic drag to explain their...

  20. Drag Torque Prediction Model for the Wet Clutches

    Institute of Scientific and Technical Information of China (English)

    HU Jibin; PENG Zengxiong; YUAN Shihua

    2009-01-01

    Reduction of drag torque in disengaged wet clutch is one of important potentials for vehicle transmission improvement. The flow of the oil film in clutch clearance is investigated. A three-dimension Navier-Stokes(N-S) equation based on laminar flow is presented to model the drag torque. Pressure and speed distribution in radial and circumferential directions are deduced. The theoretical analysis reveals that oil flow acceleration in radial direction caused by centrifugal force is the key reason for the shrinking of oil film as constant feeding flow rate. The peak drag torque occurs at the beginning of oil film shrinking. A variable is introduced to describe effective oil film area and drag torque after oil film shrinking is well evaluated with the variable. Under the working condition, tests were made to obtain drag torque curves at different clutch speed and oil viscosity. The tests confirm that simulation results agree with test data. The model performs well in the prediction of drag torque and lays a theoretical foundation to reduce it.