Stochastic Levy Divergence and Maxwell's Equations

Directory of Open Access Journals (Sweden)

B. O. Volkov

2015-01-01

Full Text Available One of the main reasons for interest in the Levy Laplacian and its analogues such as Levy d'Alembertian is a connection of these operators with gauge fields. The theorem proved by Accardi, Gibillisco and Volovich stated that a connection in a bundle over a Euclidean space or over a Minkowski space is a solution of the Yang-Mills equations if and only if the corresponding parallel transport to the connection is a solution of the Laplace equation for the Levy Laplacian or of the d'Alembert equation for the Levy d'Alembertian respectively (see [5, 6]. There are two approaches to define Levy type operators, both of which date back to the original works of Levy [7]. The first is that the Levy Laplacian (or Levy d'Alembertian is defined as an integral functional generated by a special form of the second derivative. This approach is used in the works [5, 6], as well as in the paper [8] of Leandre and Volovich, where stochastic Levy-Laplacian is discussed. Another approach to the Levy Laplacian is defining it as the Cesaro mean of second order derivatives along the family of vectors, which is an orthonormal basis in the Hilbert space. This definition of the Levy Laplacian is used for the description of solutions of the Yang-Mills equations in the paper [10].The present work shows that the definitions of the Levy Laplacian and the Levy d'Alembertian based on Cesaro averaging of the second order directional derivatives can be transferred to the stochastic case. In the article the values of these operators on a stochastic parallel transport associated with a connection (vector potential are found. In this case, unlike the deterministic case and the stochastic case of Levy Laplacian from [8], these values are not equal to zero if the vector potential corresponding to the stochastic parallel transport is a solution of the Maxwell's equations. As a result, two approaches to definition of the Levy Laplacian in the stochastic case give different operators. This

Cuckoo Search with flight of Levy applied to the problem of reload of fuels in nuclear reactors

International Nuclear Information System (INIS)

Silva, Patrick V.; Nast, Fernando N.; Schirru, Roberto; Meneses, Anderson A.M.; Coordenacao de Pos-Graduacao e Pesquisa de Engenharia

2017-01-01

Intra-Nuclear Fuel Management Optimization is a complex combinatorial problem of the NP-difficult type, associated with the refueling process of a nuclear reactor, which aims to extend the cycle of operation by determining loading patterns, obeying safety margins. In addition to the combinatorial problem, we have the aspect of calculations of reactor physics, which increases the difficult of OGCIN. Methods that are proving effective when applied to OGCIN are the algorithms belonging to the swarm intelligence paradigm. A new member of this paradigm is Cuckoo Search (CS), which has shown results promising when applied to optimization issues. The CS is based on the litter parasitism of some cuckoo species combined with the Levy flight behavior of some birds. In the present work we present the results of the application of CS to OGCIN, and compare them to the results obtained by the application of ABC

The Data of Levy and Levy (2002) ÜProspect Theory: Much Ado About Nothing?Ý Actually Support Prospect Theory

OpenAIRE

Peter P. Wakker

2003-01-01

Levy and Levy (Management Science2002) present data that, according to their claims, violate prospect theory. They suggest that prospect theory's hypothesis of an S-shaped value function, concave for gains and convex for losses, is incorrect. However, all the data of Levy and Levy are perfectly consistent with the predictions of prospect theory, as can be verified by simply applying prospect theory formulas. The mistake of Levy and Levy is that they, incorrectly, thought that probability weig...

Congestion levies; Congestieheffingen

Energy Technology Data Exchange (ETDEWEB)

Verhoef, E.T. [Vakgroep Ruimtelijke Economie, Vrije Universiteit en Tinbergen Instituut, Amsterdam (Netherlands)

1998-02-20

Traffic jams or congestion can be controlled by means of Pigouvian levies. Congestion costs comprise both time losses as scheduling costs. Because a part of those costs are external costs, the free market output is not Pareto-efficient, and therefore levies are required to recover the efficiency. With some restrictions, road-pricing for the western part of the Netherlands is considered to be a feasible option

Piaget and Levy-Bruhl.

Science.gov (United States)

Jahoda, G

2000-08-01

Levy-Bruhl exerted a powerful influence, seldom considered, on Piaget. The Levy-Bruhlian thesis of a "pre-logical mentality" characterized by "mystical participation" is outlined, together with its initial reception. The first evidence of Piaget's interest in it dates from 1920, and when he began his studies of children's thinking he compared it with that of 'primitives," also adopting Levy-Bruhl's concept of "participation." By 1928 Piaget had elaborated a theory of the social foundations of different types of thought, which he regarded as also explaining the alleged similarity between the thinking of primitives and children. Both are subject to constraint, primitives by elders and children by parents and teachers. Logical as opposed to pre-logical thought was said to depend on cooperation in free social interaction. Piaget continued to maintain essentially the same views long after Levy-Bruhl himself had renounced the notion of pre-logicality.

Who is paying for the energy levy?

International Nuclear Information System (INIS)

Kazemier, B.; Keuning, S.J.; Zijlmans, G.M.

1992-01-01

An analysis of the consequences of an energy levy should not only be aimed at the direct energy consumption (heating, lighting, engine fuels), but also on energy used for the production of goods and services, and the conversion of one energy carrier into the other. Attention is paid to the distribution of direct and indirect public purchasing power effects of three different types of levies. The levies considered here are (1) an energy levy on primary energy sources only in the Netherlands; (2) as (1) but for the whole world; and (3) an energy levy on the energy consumption of households. The effects will be best equallly spread over the households in the case of a worldwide, uniform levy. 3 tabs., 2 refs

Green taxes by doubling energy levies

International Nuclear Information System (INIS)

De Vos, R.

1998-01-01

An overview is given of green taxes, levies and investment facilities in the Netherlands. Also, attention is paid to the main issues in the Third Dutch National Environmental Plan (NMP3). Energy levies are imported for the Dutch government to shift taxes on labor further towards taxes on pollution. However, the proposed doubling of the energy levies meets strong opposition from industry and businesses. 2 fig., 3 tabs

Cuckoo Search with flight of Levy applied to the problem of reload of fuels in nuclear reactors; Busca Cuco com voo de Levy aplicado ao problema de recarga de combustiveis em reatores nucleares

Energy Technology Data Exchange (ETDEWEB)

Silva, Patrick V.; Nast, Fernando N.; Schirru, Roberto; Meneses, Anderson A.M., E-mail: patrickvs@hotmail.com, E-mail: fernandonnast@gmail.com, E-mail: anderson.meneses@pq.cnpq.br, E-mail: schirru@lmp.ufrj.br [Universidade Federal do Oeste do Para (UFOPA), Santarem, PA (Brazil). Instituto de Engenharia e Geociencias. Programa de Ciencia e Tecnologia; Coordenacao de Pos-Graduacao e Pesquisa de Engenharia (COPPE/UFRJ) RJ (Brazil). Programa de Engenharia Nuclear

2017-11-01

Intra-Nuclear Fuel Management Optimization is a complex combinatorial problem of the NP-difficult type, associated with the refueling process of a nuclear reactor, which aims to extend the cycle of operation by determining loading patterns, obeying safety margins. In addition to the combinatorial problem, we have the aspect of calculations of reactor physics, which increases the difficult of OGCIN. Methods that are proving effective when applied to OGCIN are the algorithms belonging to the swarm intelligence paradigm. A new member of this paradigm is Cuckoo Search (CS), which has shown results promising when applied to optimization issues. The CS is based on the litter parasitism of some cuckoo species combined with the Levy flight behavior of some birds. In the present work we present the results of the application of CS to OGCIN, and compare them to the results obtained by the application of ABC.

Reparametrization BRS cohomology in two-dimensional gravity and non-critical string theories

International Nuclear Information System (INIS)

Fujikawa, Kazuo.

1989-07-01

Various anomalies related to the gravitational BRS current in two-dimensional theories are explained from the view point of the path integral formalism, and the algebraic properties of composite operators are confirmed by the operator product technique. The implications of the reparametrization BRS cohomology on possible non-critical string theory are illustrated by using the string field theoretical technique. The appearance of the Higgs (or Stueckelberg)-like mechanism due to the Liouville freedom is shown. (author)

Scale-free animal movement patterns: Levy walks outperform fractional Brownian motions and fractional Levy motions in random search scenarios

International Nuclear Information System (INIS)

Reynolds, A M

2009-01-01

The movement patterns of a diverse range of animals have scale-free characteristics. These characteristics provide necessary but not sufficient conditions for the presence of movement patterns that can be approximated by Levy walks. Nevertheless, it has been widely assumed that the occurrence of scale-free animal movements can indeed be attributed to the presence of Levy walks. This is, in part, because it is known that the super-diffusive properties of Levy walks can be advantageous in random search scenarios when searchers have little or no prior knowledge of target locations. However, fractional Brownian motions (fBms) and fractional Levy motions (fLms) are both scale-free and super-diffusive, and so it is possible that these motions rather than Levy walks underlie some or all occurrences of scale-free animal movement patterns. Here this possibility is examined in numerical simulations through a determination of the searching efficiencies of fBm and fLm searches. It is shown that these searches are less efficient than Levy walk searches. This finding does not rule out the possibility that some animals with scale-free movement patterns are executing fBm and fLm searches, but it does make Levy walk searches the more likely possibility.

Primo Levi and Franz Kafka: an Unheimlich Encounter

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Stefano Bellin

2016-11-01

Full Text Available In 1983 Giulio Einaudi asked Primo Levi to translate Kafka’s Trial for the new series «Scrittori tradotti da scrittori». The proposal sounded original and provocative, and Levi accepted eagerly. The translation, however, had a negative effect on him. While working on The Trial, Levi relived his Auschwitz season, revived his deepest fears, and fell back into depression: he felt as if he was himself on trial. This was partially due to a clash of literary styles as well as to two contrasting – and yet at times kindred – conceptions of language and communication. The present study addresses the following questions: were Levi and Kafka’s literary styles as opposed as Levi implies? How is Levi’s “obscure part” connected to Kafka? Why did Levi associate The Trial with his Holocaust experience and identify himself with Josef K.? What does Levi’s encounter with Kafka tell us about the shame of being human and our capacity to give an account of ourselves? By investigating Levi’s uncanny encounter with Kafka, my essay will discuss Levi’s theory of language, showing how the Levi-Kafka intersection opens up new ways of interpreting Levi’s concerns about communication, the work of the witness, moral responsibility, and shame, which coalesced into the reflections of The Drowned and the Saved.Nel 1983 Giulio Einaudi chiese a Primo Levi di tradurre Il processo di Kafka per la nuova serie Scrittori tradotti da scrittori. La proposta parse a Levi originale ed intelligente, sicché la accettò immediatamente. La traduzione ebbe tuttavia un effetto negativo su di lui. Mentre lavorava al Processo, Levi rivisse la stagione di Auschwitz, risentì le sue più profonde paure e ricadde in depressione. Si sentiva come se fosse lui stesso processato. Ciò era in parte dovuto a due opposte concezioni di stile letterario e a due divergenti – anche se a volte paradossalmente affini – concezioni del linguaggio e della comunicazione. Il presente

Levi-Strauss : UNESCO = anthropology : politics

Directory of Open Access Journals (Sweden)

Ljiljana Gavrilović

2016-02-01

Full Text Available This paper discusses Levi-Strauss engagement in UNESCO activities. On the one hand, Levi-Strauss engagement in Pakistan had an important impact on his later work, as well as on his overall view about the world and culture( s; while on the other, Levi-Strauss’s definitions of the relationship between race/nation and culture had an important influence on the ways in which UNESCO dealt with the ideas about culture and on the ways these ideas were implemented in its global strategies of action in/towards culture. On the one hand, this engagement included a delivery of the European world view (as a superior one to everyone who does not have it; while on the other, it also meant a protection of material remains of different cultures world-wide and protection of non-material heritage and/as entire "Othern-ness", whenever it is located, and (at least in theory however it looks like. In that sense, Levi- Strauss public engagement had an important impact not only on anthropology, as a discipline that he dedicated his life to, but also to the formation of contemporary understanding of politically correct relationship towards the "Other".

Thermodynamics of strongly interacting system from reparametrized Polyakov-Nambu-Jona-Lasinio model

International Nuclear Information System (INIS)

Bhattacharyya, Abhijit; Ghosh, Sanjay K.; Maity, Soumitra; Raha, Sibaji; Ray, Rajarshi; Saha, Kinkar; Upadhaya, Sudipa

2017-01-01

The Polyakov-Nambu-Jona-Lasinio model has been quite successful in describing various qualitative features of observables for strongly interacting matter, that are measurable in heavy-ion collision experiments. The question still remains on the quantitative uncertainties in the model results. Such an estimation is possible only by contrasting these results with those obtained from rst principles using the lattice QCD framework. Recently a variety of lattice QCD data were reported in the realistic continuum limit. Here we make a first attempt at reparametrizing the model so as to reproduce these lattice data

Endogenous enforcement and effectiveness of China's pollution levy system

OpenAIRE

Hua Wang; Wheeler, David

2000-01-01

The authors investigate two aspects of China's pollution levy system, which was first implemented about 20 years ago. First, they analyze what determines differences in enforcement of the pollution levy in various urban areas. They find that collection of the otherwise uniform pollution levy is sensitive to differences in economic development and environmental quality. Air and water pollution levies are higher in areas that are heavily polluted. Second, they analyze the impact of pollution ch...

27 CFR 70.162 - Levy and distraint on salary and wages.

Science.gov (United States)

2010-04-01

... salary and wages. 70.162 Section 70.162 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX... § 70.162 Levy and distraint on salary and wages. (a) Notice of intent to levy. Levy may be made for any... salary or wages. A levy on salary or wages is continuous from the time of the levy until the liability...

The Influence of the Number of Different Stocks on the Levy-Levy-Solomon Model

Science.gov (United States)

Kohl, R.

The stock market model of Levy, Levy, Solomon is simulated for more than one stock to analyze the behavior for a large number of investors. Small markets can lead to realistic looking prices for one and more stocks. A large number of investors leads to a semi-regular fashion simulating one stock. For many stocks, three of the stocks are semi-regular and dominant, the rest is chaotic. Aside from that we changed the utility function and checked the results.

On the existence of Levi Foliations

Directory of Open Access Journals (Sweden)

RENATA N. OSTWALD

2001-03-01

Full Text Available Let L be a real 3 dimensional analytic variety. For each regular point p L there exists a unique complex line l p on the space tangent to L at p. When the field of complex line p l p is completely integrable, we say that L is Levi variety. More generally; let L M be a real subvariety in an holomorphic complex variety M. If there exists a real 2 dimensional integrable distribution on L which is invariant by the holomorphic structure J induced by M, we say that L is a Levi variety. We shall prove: Theorem. Let be a Levi foliation and let be the induced holomorphic foliation. Then, admits a Liouvillian first integral. In other words, if is a 3 dimensional analytic foliation such that the induced complex distribution defines an holomorphic foliation ; that is, if is a Levi foliation; then admits a Liouvillian first integral--a function which can be constructed by the composition of rational functions, exponentiation, integration, and algebraic functions (Singer 1992. For example, if f is an holomorphic function and if theta is real a 1-form on ; then the pull-back of theta by f defines a Levi foliation : f*theta = 0 which is tangent to the holomorphic foliation : df = 0. This problem was proposed by D. Cerveau in a meeting (see Fernandez 1997.Seja L Ì uma variedade real de dimensão 3. Para todo ponto regular p Î L existe uma única reta complexa l p no espaço tangente à L em p. Quando o campo de linhas complexas p l p é completamente integrável, dizemos que L é uma variedade de Levi. Mais geralmente, seja L Ì M uma subvariedade real em uma variedade analítica complexa. Se existe uma distribuição real integrável de dimensão 2 em L que é invariante pela estrutura holomorfa J induzida pela variedade complexa M, dizemos que L é uma variedade de Levi. Vamos provar: Teorema. Seja uma folheação de Levi e seja a folheação holomorfa induzida. Então tem integral primeira Liouvilliana. Em outras palavras, se é uma folheação real de

Extreme events as foundation of Levy walks with varying velocity

International Nuclear Information System (INIS)

Kutner, Ryszard

2002-01-01

In this work we study the role of extreme events [E.W. Montroll, B.J. West, in: J.L. Lebowitz, E.W. Montrell (Eds.), Fluctuation Phenomena, SSM, vol. VII, North-Holland, Amsterdam, 1979, p. 63; J.-P. Bouchaud, M. Potters, Theory of Financial Risks from Statistical Physics to Risk Management, Cambridge University Press, Cambridge, 2001; D. Sornette, Critical Phenomena in Natural Sciences. Chaos, Fractals, Selforganization and Disorder: Concepts and Tools, Springer, Berlin, 2000] in determining the scaling properties of Levy walks with varying velocity. This model is an extension of the well-known Levy walks one [J. Klafter, G. Zumofen, M.F. Shlesinger, in M.F. Shlesinger, G.M. Zaslavsky, U. Frisch (Eds.), Levy Flights and Related Topics ion Physics, Lecture Notes in Physics, vol. 450, Springer, Berlin, 1995, p. 196; G. Zumofen, J. Klafter, M.F. Shlesinger, in: R. Kutner, A. Pekalski, K. Sznajd-Weron (Eds.), Anomalous Diffusion. From Basics to Applications, Lecture Note in Physics, vol. 519, Springer, Berlin, 1999, p. 15] introduced in the context of chaotic dynamics where a fixed value of the walker velocity is assumed for simplicity. Such an extension seems to be necessary when the open and/or complex system is studied. The model of Levy walks with varying velocity is spanned on two coupled velocity-temporal hierarchies: the first one consisting of velocities and the second of corresponding time intervals which the walker spends between the successive turning points. Both these hierarchical structures are characterized by their own self-similar dimensions. The extreme event, which can appear within a given time interval, is defined as a single random step of the walker having largest length. By finding power-laws which describe the time-dependence of this displacement and its statistics we obtained two independent diffusion exponents, which are related to the above-mentioned dimensions and which characterize the extreme event kinetics. In this work we show the

The quantum Levy walk

International Nuclear Information System (INIS)

Caceres, Manuel O; Nizama, Marco

2010-01-01

We introduce the quantum Levy walk to study transport and decoherence in a quantum random model. We have derived from second-order perturbation theory the quantum master equation for a Levy-like particle that moves along a lattice through scale-free hopping while interacting with a thermal bath of oscillators. The general evolution of the quantum Levy particle has been solved for different preparations of the system. We examine the evolution of the quantum purity, the localized correlation and the probability to be in a lattice site, all of them leading to important conclusions concerning quantum irreversibility and decoherence features. We prove that the quantum thermal mean-square displacement is finite under a constraint that is different when compared to the classical Weierstrass random walk. We prove that when the mean-square displacement is infinite the density of state has a complex null-set inside the Brillouin zone. We show the existence of a critical behavior in the continuous eigenenergy which is related to its non-differentiability and self-affine characteristics. In general, our approach allows us to study analytically quantum fluctuations and decoherence in a long-range hopping model.

Correlated Levy Noise in Linear Dynamical Systems

International Nuclear Information System (INIS)

Srokowski, T.

2011-01-01

Linear dynamical systems, driven by a non-white noise which has the Levy distribution, are analysed. Noise is modelled by a specific stochastic process which is defined by the Langevin equation with a linear force and the Levy distributed symmetric white noise. Correlation properties of the process are discussed. The Fokker-Planck equation driven by that noise is solved. Distributions have the Levy shape and their width, for a given time, is smaller than for processes in the white noise limit. Applicability of the adiabatic approximation in the case of the linear force is discussed. (author)

Levy-free part in energy tax is not wanted

International Nuclear Information System (INIS)

Gilijamse, W.

1995-01-01

The Dutch government proposed to implement an energy levy for small-scale consumers in 1996. The yields will be reimbursed by means of a reduction of the tax burden. By applying a levy-free tax allowance the tax reduction can be limited. However, it appears that this allowance does not work: it reduces the energy saving impact of the energy levy, because it does not stimulate investments in energy saving housing construction and energy saving heat supply. It also interferes with a just compensation of income. It is recommended to cancel the levy-free tax allowance and to realize compensation by raising the tax free allowance in the income tax. 2 figs., 1 tab., 6 refs

48 CFR 252.225-7033 - Waiver of United Kingdom levies.

Science.gov (United States)

2010-10-01

... waiver of levies included in the price of this contract, the U.S. Government reserves the right to reduce the contract price by the amount of the levy waived plus associated indirect costs and profit or fee... attempt to obtain a waiver of any commercial exploitation levies included in the price of this contract...

Satellite orbits in Levi-Civita space

Science.gov (United States)

Humi, Mayer

2018-03-01

In this paper we consider satellite orbits in central force field with quadratic drag using two formalisms. The first using polar coordinates in which the satellite angular momentum plays a dominant role. The second is in Levi-Civita coordinates in which the energy plays a central role. We then merge these two formalisms by introducing polar coordinates in Levi-Civita space and derive a new equation for satellite orbits which unifies these two paradigms. In this equation energy and angular momentum appear on equal footing and thus characterize the orbit by its two invariants. Using this formalism we show that equatorial orbits around oblate spheroids can be expressed analytically in terms of Elliptic functions. In the second part of the paper we derive in Levi-Civita coordinates a linearized equation for the relative motion of two spacecrafts whose trajectories are in the same plane. We carry out also a numerical verification of these equations.

Energy levy and consequences for the incomes

International Nuclear Information System (INIS)

De Kam, C.A.

1992-01-01

Attention is paid to levies proposed for the domestic energy consumption in the Netherlands. Possibilities to compensate households for such levies by means of burden reductions are discussed. Given the starting point of the present Dutch coalition agreement that the macro-economic level of levies should not increase, a compensating reduction of the Value Added Tax (VAT) or the income tax seems to be the most obvious measure. Considering the large diversity in the energy consumption of households it is impossible to compensate precisely every household via such general measures. Moreover, this is actual undesirable, because otherwise the stimulus to save energy will be lost. However, a compensation, that will leave the personal income distribution on the whole unaltered, should be feasible. 1 fig., 4 tabs., 14 refs

ECONOMY AND PARA-FISCAL LEVIES IN BOSNIA AND HERZEGOVINA

Directory of Open Access Journals (Sweden)

Hasan Mahmutović

2017-04-01

Full Text Available The system of para-fiscal levies implies different types of benefits or compensation and payment of citizens and companies for the use of goods or services of state administration which are para-fiscal sources of income of the state. The main characteristics of para-fiscal levies are: they do not originate from all tax payers, but only from members of certain social groups that are linked to some common economic or social interests; they are not part of the budget funds and not regulate them fiscal authorities; they have the character of destined public revenues, as they regularly represent a dedicated revenue whit which a specific task of economic or social character would be solved; they represent a secondary tax levy, which means that they exist along with the country’s tax levy, to draw funds from the same economic resources and to have almost the same economic effects, as well as the collection of taxes; they shall be paid on the basis of laws and decisions or decision of the competent authorities (general obligation or by contract (a specific levy, ie. an individual obligation; they shall be paid in the event of use of property of general interest and / or services of state administration; they represent giving of money, which is always direct, ie. giving cash on the basis of the decision and with the issuance of a receipt of payment (receipt from a box office or bank. Para-fiscal levies should be understood as fees that economic operators and citizens pay for the use of certain goods or services. These are not taxes and they do not serve to fill the budget. However, in Bosnia and Herzegovina the biggest part of para-fiscal levies is used as a parallel budget revenue, as revenue for the operation of the costly administrative apparatus. A large number of studies on para-fiscal levies in Bosnia and Herzegovina showed that they have a negative impact on economic growth and development. Basically para-fiscal levies, for business entities at

Basics of Swiss water levy politics - Legal aspects; Grundlagen Wasserzinspolitik. Rechtliche Ueberlegungen - Schlussbericht

Energy Technology Data Exchange (ETDEWEB)

Leimbacher, J.

2008-10-15

This comprehensive final report for the Swiss Federal Office of Energy (SFOE) takes a look at the legal aspects involved in setting up the basics for the definition of the interest to be levied on water commodities. This levy is raised in Switzerland on the use of water and represents the payment made to a commune for the use of its water resources. The original aims of the levy, to encourage the use of water resources, are noted. Limits on the height of the levy and the definition and adjustment of the maximum rate by government are discussed. Various legal aspects are examined and the fact that the levy must be economically reasonable and economically acceptable is discussed. Various pragmatic approaches to being able to adjust or index the levy are discussed. The introduction of an additional levy to cover the storage of water is discussed, as is the definition of the part use of the proceeds to provide funding for the high-voltage electricity grid, for example. The history of the levy and various political initiatives are noted and even the abolition of the levy is discussed.

26 CFR 301.6331-1 - Levy and distraint.

Science.gov (United States)

2010-04-01

... intangible, belonging to the taxpayer. The district director may also levy upon property with respect to...), the 30-day period provided in section 6331(d), or the limitation on levy provided in section 6331(g)(1... either a Federal or a State court, the assets of the taxpayer are in general under the control of the...

Make the Alberta Carbon Levy Revenue Neutral

Directory of Open Access Journals (Sweden)

Kenneth J. McKenzie

2016-04-01

Full Text Available The new carbon levy of $30 per tonne, announced in November 2015 as part of the report issued by the Alberta government’s Climate Leadership Panel, is a positive move in the direction of pricing carbon emissions. The levy is expected to generate $3 billion in net revenue by 2018, and possibly as much as $5 billion by 2030. While there is some discussion in the report of what should be done with the revenues generated by the carbon levy, it is somewhat vague on the details, leaving a number of options open to the government. The purpose of this briefing paper is to argue that the revenues from the carbon levy should be used to lower existing taxes – the carbon tax should be revenue neutral, generating no new net revenue for the government. The basic argument is that the carbon levy can be viewed through two lenses. The first lens is the imposition of a price on carbon emissions which (at least partly reflects the social costs of emissions. Viewed through this price lens, the carbon levy plays an important role in incenting firms and individuals to change their behaviour and move towards less carbon intensive activities. The second lens is the role of a carbon tax as a part of the broad revenue system. Viewed through this tax lens, a carbon tax is not a very good, or efficient, way of generating revenue. The reason for this is somewhat nuanced, but the basic idea is that the carbon tax is applied to a narrower base than broader-based taxes. Broad based taxes generally impose lower costs on the economy than narrow based taxes. Moreover, carbon taxes interact with other taxes in the economy, exacerbating the economic costs associated with those taxes. And those costs are quite high – research shows that the total cost to the economy of raising an additional $1 in revenue through the corporate income tax in Alberta is $3.79; for the personal income tax the cost is $1.71. These taxes therefore impose higher costs on the economy than they raise

The economic consequences of a fuel levy reform in South Africa

Directory of Open Access Journals (Sweden)

Ramos Mabugu

2011-06-01

Full Text Available This paper assesses the economic effects of a hypothetical fuel levy imposed by South African provinces. The welfare effects of increasing the fuel levy by 10 per cent are negative but very small. Similarly, the marginal excess burdens for efficiency and equity (poverty are quite low, suggesting much smaller impacts of the intervention on both economic activity and equity.  Furthermore, a fiscal policy reform that raises fuel levy by 10 per cent is progressive as it has stronger negative effects on higher income households than the lower income households. A potential source of instability for the macroeconomy and total government revenue is the negative effect on economic activity induced by the fuel levy increase. The remedies suggested are that policymakers should make tax room elsewhere in the intergovernmental fiscal system to accommodate the fuel levy increase.

Zimbabwe's national AIDS levy: A case study.

Science.gov (United States)

Bhat, Nisha; Kilmarx, Peter H; Dube, Freeman; Manenji, Albert; Dube, Medelina; Magure, Tapuwa

2016-01-01

We conducted a case study of the Zimbabwe National AIDS Trust Fund ('AIDS Levy') as an approach to domestic government financing of the response to HIV and AIDS. Data came from three sources: a literature review, including a search for grey literature, review of government documents from the Zimbabwe National AIDS Council (NAC), and key informant interviews with representatives of the Zimbabwean government, civil society and international organizations. The literature search yielded 139 sources, and 20 key informants were interviewed. Established by legislation in 1999, the AIDS Levy entails a 3% income tax for individuals and 3% tax on profits of employers and trusts (which excluded the mining industry until 2015). It is managed by the parastatal NAC through a decentralized structure of AIDS Action Committees. Revenues increased from inception to 2006 through 2008, a period of economic instability and hyperinflation. Following dollarization in 2009, annual revenues continued to increase, reaching US$38.6 million in 2014. By policy, at least 50% of funds are used for purchase of antiretroviral medications. Other spending includes administration and capital costs, HIV prevention, and monitoring and evaluation. Several financial controls and auditing systems are in place. Key informants perceived the AIDS Levy as a 'homegrown' solution that provided country ownership and reduced dependence on donor funding, but called for further increased transparency, accountability, and reduced administrative costs, as well as recommended changes to increase revenue. The Zimbabwe AIDS Levy has generated substantial resources, recently over US$35 million per year, and signals an important commitment by Zimbabweans, which may have helped attract other donor resources. Many key informants considered the Zimbabwe AIDS Levy to be a best practice for other countries to follow.

Levy's zero-one law in game-theoretic probability

OpenAIRE

Shafer, Glenn; Vovk, Vladimir; Takemura, Akimichi

2009-01-01

We prove a game-theoretic version of Levy's zero-one law, and deduce several corollaries from it, including non-stochastic versions of Kolmogorov's zero-one law, the ergodicity of Bernoulli shifts, and a zero-one law for dependent trials. Our secondary goal is to explore the basic definitions of game-theoretic probability theory, with Levy's zero-one law serving a useful role.

Final report of the Steering Group Regulating Energy Levies

International Nuclear Information System (INIS)

Wolfson, D.J.; Frijns, J.M.G.; Opschoor, J.B.; Rissik, S.A.; Stevens, L.G.M.

1992-02-01

The aim is to determine to what extent regulating energy levies can generate energy savings, and to gain insight into the economic impacts of energy levies. Special attention is paid to the consequences for the competitive position and the development of economic and industrial activities, employment, distribution of incomes and purchasing power. An indication is given to what extent policy tools for regulating energy levies meet the criteria for efficiency, effectivity and legitimacy. Three hypothetic measures to map the energy saving effects and economic side-effects are discussed for two tax-levels: 50% and 100%. Variant A is a fixed levy on all the primary energy carriers, implemented on an OECD-level, equally based on the carbon content and the energy content. Variant B is the same as variant A, but only implemented in the Netherlands. Variant C is a fixed levy on the energy consumption of small energy consumers in the Netherlands, which variant spares and protects the energy-intensive industry. In the chapters 5, 6 and 7 the results of preliminary studies on price elasticities and energy consumption in the road traffic sector, households, and housing construction are discussed, as well as energy conservation in the rental sector and the Dutch production economies, and the competitive impacts of energy levies on industry and business in the Netherlands. In chapter 8 and 9 possibilities to reimburse the revenues to the government, the businesses or industries, and the households, are mentioned and considered. Attention is paid to the financial consequences and the impacts on spending power. In chapter (10) the economic effects of the levy variants, as calculated by the Centraal Plan Bureau (CPB, Dutch government institute for economic planning), are described. Variant A will result in substantial negative economic effects: loss of income and a limited growth of employment, caused by transfer of part of the energy-intensive industry to outside the OECD

On the generation of log-Levy distributions and extreme randomness

International Nuclear Information System (INIS)

Eliazar, Iddo; Klafter, Joseph

2011-01-01

The log-normal distribution is prevalent across the sciences, as it emerges from the combination of multiplicative processes and the central limit theorem (CLT). The CLT, beyond yielding the normal distribution, also yields the class of Levy distributions. The log-Levy distributions are the Levy counterparts of the log-normal distribution, they appear in the context of ultraslow diffusion processes, and they are categorized by Mandelbrot as belonging to the class of extreme randomness. In this paper, we present a natural stochastic growth model from which both the log-normal distribution and the log-Levy distributions emerge universally-the former in the case of deterministic underlying setting, and the latter in the case of stochastic underlying setting. In particular, we establish a stochastic growth model which universally generates Mandelbrot's extreme randomness. (paper)

Eesti allilm suudab tõkestada GSM-levi / Rasmus Kagge

Index Scriptorium Estoniae

Kagge, Rasmus, 1977-

2006-01-01

Ilmunud ka: Postimees : na russkom jazõke 10. mai lk. 2. Politsei andmetel on Eesti kuritegelike jõukude käes praegu vähemalt paar GSM-levi segajat ehk jammerit. Politseil on õnnestunud konfiskeerida autovarastelt üks GSM-levi tõkestaja. Lisa. Kasutajapiirang. Vt. samas: Jammereid saab osta internetist

Tax levy financing for local public health: fiscal allocation, effort, and capacity.

Science.gov (United States)

Riley, William J; Gearin, Kimberly J; Parrotta, Carmen D; Briggs, Jill; Gyllstrom, M Elizabeth

2013-12-01

Local health departments (LHDs) rely on a wide variety of funding sources, and the level of financing is associated with both LHD performance in essential public health services and population health outcomes. Although it has been shown that funding sources vary across LHDs, there is no evidence regarding the relationship between fiscal allocation (local tax levy); fiscal effort (tax capacity); and fiscal capacity (community wealth). The purpose of this study is to analyze local tax levy support for LHD funding. Three research questions are addressed: (1) What are tax levy trends in LHD fiscal allocation? (2) What is the role of tax levy in overall LHD financing? and (3) How do local community fiscal capacity and fiscal effort relate to LHD tax levy fiscal allocation? This study focuses on 74 LHDs eligible for local tax levy funding in Minnesota. Funding and expenditure data for 5 years (2006 to 2010) were compiled from four governmental databases, including the Minnesota Department of Health, the State Auditor, the State Demographer, and the Metropolitan Council. Trends in various funding sources and expenditures are described for the time frame of interest. Data were analyzed in 2012. During the 2006-2010 time period, total average LHD per capita expenditures increased 13%, from $50.98 to $57.63. Although the overall tax levy increase in Minnesota was 25%, the local tax levy for public health increased 5.6% during the same period. There is a direct relationship between fiscal effort and LHD expenditures. Local funding reflects LHD community priorities and the relative importance in comparison to funding other local programs with tax dollars. In Minnesota, local tax levy support for local public health services is not keeping pace with local tax support for other local government services. These results raise important questions about the relationship between tax levy resource effort, resource allocation, and fiscal capacity as they relate to public health

Management of Operational Support Requirements for Manned Flight Missions

Science.gov (United States)

1991-01-01

This Instruction establishes responsibilities for managing the system whereby operational support requirements are levied for support of manned flight missions including associated payloads. This management system will ensure that support requirements are properly requested and responses are properly obtained to meet operational objectives.

Ricordare per interrogare: Percorsi della memoria in Primo Levi ...

African Journals Online (AJOL)

This commemorative essay traces the function of memory and the relation between memory and imagination in the works of Primo Levi. It looks at the common matrix and the subtle link between Levi works of testimony and his fictional writings, suggesting that his fantasy and science fiction stories be read as metaphors or ...

Anomalous diffusion and Levy random walk of magnetic field lines in three dimensional turbulence

International Nuclear Information System (INIS)

Zimbardo, G.; Veltri, P.; Basile, G.; Principato, S.

1995-01-01

The transport of magnetic field lines is studied numerically where three dimensional (3-D) magnetic fluctuations, with a power law spectrum, and periodic over the simulation box are superimposed on an average uniform magnetic field. The weak and the strong turbulence regime, δB∼B 0 , are investigated. In the weak turbulence case, magnetic flux tubes are separated from each other by percolating layers in which field lines undergo a chaotic motion. In this regime the field lines may exhibit Levy, rather than Gaussian, random walk, changing from Levy flights to trapped motion. The anomalous diffusion laws left-angle Δx 2 i right-angle ∝s α with α>1 and α<1, are obtained for a number of cases, and the non-Gaussian character of the field line random walk is pointed out by computing the kurtosis. Increasing the fluctuation level, and, therefore stochasticity, normal diffusion (α congruent 1) is recovered and the kurtoses reach their Gaussian value. However, the numerical results show that neither the quasi-linear theory nor the two dimensional percolation theory can be safely extrapolated to the considered 3-D strong turbulence regime. copyright 1995 American Institute of Physics

Decoupling of the reparametrization degree of freedom and a generalized probability in quantum cosmology

Science.gov (United States)

Dimakis, N.; Terzis, Petros A.; Zampeli, Adamantia; Christodoulakis, T.

2016-09-01

The high degree of symmetry renders the dynamics of cosmological as well as some black hole spacetimes describable by a system of finite degrees of freedom. These systems are generally known as minisuperspace models. One of their important key features is the invariance of the corresponding reduced actions under reparametrizations of the independent variable, a fact that can be seen as the remnant of the general covariance of the full theory. In the case of a system of n degrees of freedom, described by a Lagrangian quadratic in velocities, one can use the lapse by either gauge fixing it or letting it be defined by the constraint and subsequently substitute into the rest of the equations. In the first case, the system of the second-order equations of motion is solvable for all n accelerations and the constraint becomes a restriction among constants of integration. In the second case, the system can be solved for only n -1 accelerations and the "gauge" freedom is transferred to the choice of one of the scalar degrees of freedom. In this paper, we take the second path and express all n -1 scalar degrees of freedom in terms of the remaining one, say q . By considering these n -1 degrees of freedom as arbitrary but given functions of q , we manage to extract a two-dimensional pure gauge system consisting of the lapse N and the arbitrary q : in a way, we decouple the reparametrization invariance from the rest of the equations of motion, which are thus describing the "true" dynamics. The solution of the corresponding quantum two-dimensional system is used for the definition of a generalized probability for every configuration fi(q ), be it classical or not. The main result is that, interestingly enough, this probability attains its extrema on the classical solution of the initial n -dimensional system.

The Levy sections theorem revisited

International Nuclear Information System (INIS)

Figueiredo, Annibal; Gleria, Iram; Matsushita, Raul; Silva, Sergio Da

2007-01-01

This paper revisits the Levy sections theorem. We extend the scope of the theorem to time series and apply it to historical daily returns of selected dollar exchange rates. The elevated kurtosis usually observed in such series is then explained by their volatility patterns. And the duration of exchange rate pegs explains the extra elevated kurtosis in the exchange rates of emerging markets. In the end, our extension of the theorem provides an approach that is simpler than the more common explicit modelling of fat tails and dependence. Our main purpose is to build up a technique based on the sections that allows one to artificially remove the fat tails and dependence present in a data set. By analysing data through the lenses of the Levy sections theorem one can find common patterns in otherwise very different data sets

The Levy sections theorem revisited

Science.gov (United States)

Figueiredo, Annibal; Gleria, Iram; Matsushita, Raul; Da Silva, Sergio

2007-06-01

This paper revisits the Levy sections theorem. We extend the scope of the theorem to time series and apply it to historical daily returns of selected dollar exchange rates. The elevated kurtosis usually observed in such series is then explained by their volatility patterns. And the duration of exchange rate pegs explains the extra elevated kurtosis in the exchange rates of emerging markets. In the end, our extension of the theorem provides an approach that is simpler than the more common explicit modelling of fat tails and dependence. Our main purpose is to build up a technique based on the sections that allows one to artificially remove the fat tails and dependence present in a data set. By analysing data through the lenses of the Levy sections theorem one can find common patterns in otherwise very different data sets.

The data of Lelvy and Levy , "Prospect theory: much ado about nothing??", support prospect theory

NARCIS (Netherlands)

Wakker, P.P.

2003-01-01

Levy and Levy (Management Science, 2002) present data that, according to their claims, violate prospect theory. They suggest that prospect theoryys hypothesis of an S-shaped value function, concave for gains and convex for losses, is incorrect. However, all of the data of Levy and Levy are perfectly

Una complessa chiarezza: gli ipertesti di Primo Levi

Directory of Open Access Journals (Sweden)

Tommaso Pepe

2016-11-01

Full Text Available Scrittore poliedrico e versatile, Primo Levi è stato anche un costruttore di estesi e articolati ipertesti: strutture macrotestuali fondate su legami e interrelazioni tese fra opere cronologicamente e tipologicamente differenziate. Un esempio straordinario, ma non certo isolato, di questa scrittura di secondo grado, organizzata in complessi palinsesti testuali, è quello che già Marco Belpoliti ha definito nei termini di «macrotesto del Lager»: un reticolo intra- e intertestuale che, a partire da Se questo è un uomo, si è sviluppato con un andamento rizomatico attraverso diverse stratificazioni scrittorie e genealogiche, sino a I sommersi e i salvati. Il «rizoma» tuttavia è semplicemente una delle varie macrostrutture individuabili nell’opera di Levi. Attraverso un confronto contrastivo con l’opera di Calvino, il saggio si propone di indagare alcune delle caratteristiche salienti di questa scrittura ipertestuale, mostrando come l’intensa sperimentazione scrittoria perseguita da Levi sia da ricollegarsi a una parallela svolta epistemologica, data dall’insorgere di quella che Edgar Morin ha definito come «sfida della complessità».Primo Levi can be considered a versatile and polyhedral writer, capable of building long and articulated hypertexts, i.e., macrotextual structures based on the links and interrelations among works which differ both from a chronological and typological point of view. An extraordinary, but certainly not isolated, example of this writing, organized according to complex textual palimpsests, is the one that Marco Belpoliti defined as the «macrotext of the Lager»: it is an intra- and intertextual network that, starting from If This is a Man, developed according to a rhizomatic structure through his different works and genealogical stratifications, ending with The Drowned and the Saved. The «rhizome», however, is only one of the different macrostructures which may be singled out in Levi’s work. By

UK's climate change levy: cost effectiveness, competitiveness and environmental impacts

International Nuclear Information System (INIS)

Varma, Adarsh

2003-01-01

This paper intends to examine the cost effectiveness of UK's climate change levy (CCL), its implications on competitiveness of firms and the environmental impact. The paper briefly describes the levy and analyses it under the cannons of a good taxation policy. The economic implications of the levy are discussed with theoretical and empirical perspectives. Change in net exports, investment patterns and productivity and inclusion of compliance cost forms the basis for analysing the effect on competitiveness. It discusses the options available to firms to safeguard their competitiveness if it is adversely affected by the CCL. A description of the current scenario of the levy since its inception is also presented. The paper argues the need for a comprehensive policy involving the use of standards, emission trading as well as energy taxes to achieve emission and energy-use reductions. A focal point of this paper is to elucidate the pros and cons of the CCL (energy tax) with respect to an emission trading scheme

On levies to reduce the nitrogen surplus: the case of Dutch pig farms.

NARCIS (Netherlands)

Fontein, P.; Thijssen, G.; Magnus, J.; Dijk, J.

1994-01-01

Pig farms in the Netherlands pay a zero or low price for using the environment. As a consequence, the environment is overused. The Dutch government wants to reduce the emissions of nitrogen and phosphorus. Possible instruments are regulation and levies. In this study a levy on feed and a levy on the

Mixtures in nonstable Levy processes

International Nuclear Information System (INIS)

Petroni, N Cufaro

2007-01-01

We analyse the Levy processes produced by means of two interconnected classes of nonstable, infinitely divisible distribution: the variance gamma and the Student laws. While the variance gamma family is closed under convolution, the Student one is not: this makes its time evolution more complicated. We prove that-at least for one particular type of Student processes suggested by recent empirical results, and for integral times-the distribution of the process is a mixture of other types of Student distributions, randomized by means of a new probability distribution. The mixture is such that along the time the asymptotic behaviour of the probability density functions always coincide with that of the generating Student law. We put forward the conjecture that this can be a general feature of the Student processes. We finally analyse the Ornstein-Uhlenbeck process driven by our Levy noises and show a few simulations of it

Classification of finite reparametrization symmetry groups in the three-Higgs-doublet model

International Nuclear Information System (INIS)

Ivanov, Igor P.; Vdovin, E.

2013-01-01

Symmetries play a crucial role in electroweak symmetry breaking models with non-minimal Higgs content. Within each class of these models, it is desirable to know which symmetry groups can be implemented via the scalar sector. In N-Higgs-doublet models, this classification problem was solved only for N=2 doublets. Very recently, we suggested a method to classify all realizable finite symmetry groups of Higgs-family transformations in the three-Higgs-doublet model (3HDM). Here, we present this classification in all detail together with an introduction to the theory of solvable groups, which play the key role in our derivation. We also consider generalized-CP symmetries, and discuss the interplay between Higgs-family symmetries and CP-conservation. In particular, we prove that presence of the Z 4 symmetry guarantees the explicit CP-conservation of the potential. This work completes classification of finite reparametrization symmetry groups in 3HDM. (orig.)

Greening of taxes and energy. Effects of increased energy levies and specific exemptions

International Nuclear Information System (INIS)

1997-06-01

The study on the title subject is part of a new long-term outlook for the period 1990-2020, focusing on the environment, mobility, space (physical planning) and energy. The environmental, employment and economic impacts of two levy variants have been analyzed. The first is the so-called Regulating Energy Levy (REB, abbreviated in Dutch), and the second is the Environment-Based Tax Law (WBM, abbreviated in Dutch). Tax rebates to households and businesses are in the form of a lower income tax and lower employer contributions. It is concluded that it is possible to double existing energy levies or to triple them for small-scale consumers without large economic impacts, provided that (1) large-scale consumers are spared; (2) the levies are rebated totally or partly; and (3) levy and rebate will be accepted by the Dutch society

The economics of the CDM levy: Revenue potential, tax incidence and distortionary effects

International Nuclear Information System (INIS)

Fankhauser, Samuel; Martin, Nat

2010-01-01

A levy on the Clean Development Mechanism and other carbon trading schemes is a potential source of finance for climate change adaptation. An adaptation levy of 2% is currently imposed on all CDM transactions which could raise around $500 million between now and 2012. This paper analyses the scope for raising further adaptation finance from the CDM, the economic costs (deadweight loss) of such a measure and the incidence of the levy, that is, the economic burden the levy would impose on the buyers and sellers of credits. We find that a levy of 2% could raise up to $2 billion a year in 2020 if there are no restrictions on demand. This could rise to $10 billion for a 10% tax. Restrictions on credit demand (called supplementarity limits, the requirement that most emission abatement should happen domestically) curtail trade volumes and consequently tax revenues. They also alter the economic impact of the CDM levy. Without supplementarity restrictions sellers (developing countries) bear two-thirds of the cost of the tax. If there are supplementarity limits they can pass on the tax burden to buyers (developed countries) more or less in full. Without supplementarity restrictions the distortionary effect of the levy (its deadweight loss) rises sharply with the tax rate. With them the deadweight loss is close to zero.

Levi-Strauss and the Opera

Directory of Open Access Journals (Sweden)

Vlado Kotnik

2016-02-01

Full Text Available This paper is dedicated to Claude Levi-Strauss and his structural reading of opera as metaphorical ‘composing’ of an anthropological grand opera, materialized in the four-volume study of Mythologiques, which refers to Wagner’s tetralogy of The Ring. He created a type of comparative view of the function and structure of myth schemes in Amerindian culture and the orchestral scores of Wagner’s operas, and implicitly signalled that European music, with its eminent representation – opera – has had the same value or similar symbolic position in the mind and life of a contemporary European that myth has had in ‘the savage mind’. Through this, he can lead us to the understanding of opera as myth and metaphor. However, the paper extends the discussion on Levi-Strauss to a broader historical picture of the relationship between opera and mythology as two symbolic systems of European culture.

Participation of firms in the skills development levy system

Directory of Open Access Journals (Sweden)

GJ Lee

2004-04-01

Full Text Available Skills development levies are increasingly being utilised to increase enterprise provided training in developing economies. South Africa is one such example. The impact of such incentive systems on the bottom-line of firms is a vital consideration in such programs. Particularly important are the economic conditions under which the incentive will stimulate participation by organisations. The transaction costs of participation must be taken into account: while a levy-grant system clearly creates a prima-facie incentive, it may be prohibitively expensive for some firms to enter the grant disbursement systems. Accordingly, through a simple model of the incentives for firms, the participation level of the firm under various types of levy systems is assessed. Non-monetary considerations are also considered. The implications for participation by firms, along with managerial and policy implications, are discussed.

[An illustrious unknown. Giuseppe Levi among science, anti-fascism and Nobel Prizes].

Science.gov (United States)

Grignolio, Andrea; De Sio, Fabio

2009-01-01

The anatomist Giuseppe Levi (1872-1965) is unanimously considered one of the major figures of Italian biomedical sciences in the 20th century. His fame, however, is mainly derived from having nurtured three Nobel Prize winners, namely Salvador E. Luria, Rita Levi Montalcini and Renato Dulbecco. In reappraising Levi's role in the development of Italian science and culture in general, this article aims at questioning both the narrowness of earlier accounts and a certain kind of genealogical approach to the history of scientific disciplines and academic schools. We will here consider Giuseppe Levi as an instance of two major cultural phenomena: the development of experimental biology in Italy and continental Europe and the anti-fascist socialist culture expressed by a part of the Italian intellectuals. In so doing, we will reassess the historical specificity of the scientific maturation of Levi's three famous students, on the one hand, while on the other we will consider in some depth the cultural and moral environment in which Levi thrived and his role as a moral example for his students. Such revision, we will argue, have a direct bearing on more general historiographical issues, namely, the need for a stronger contextualization of the birth and consolidation of research traditions, implying a rejection of simplistic genealogical reconstructions, and the role of academic schools and institutional settings in the definition of novel, multidisciplinary scientific approaches. Finally, the following will highlight the importance of a more careful outlook on the master-pupil relationship in academic context, addressing issues of both continuity and rupture. The article is subdivided in two main sections, the first devoted to Levi as a scientist, the second to his Anti-fascism.

Energy Efficiency instead of CO2 levy

International Nuclear Information System (INIS)

Uetz, R.

2005-01-01

This article takes a look at ways of avoiding a future, planned Swiss CO 2 levy by improving the efficiency of energy use. The political situation concerning the reduction of CO 2 emissions in Switzerland is reviewed and the likeliness of the introduction of a CO 2 levy is discussed. Strategies for the reduction of fossil fuel consumption and therefore of CO 2 emissions are looked at, including process optimisation. Recommendations are made on how to approach this work systematically - data collection, assessment of the potential for reduction and the planning of measures to be taken are looked at. The high economic efficiency of immediate action is stressed and typical middle and long-term measures are listed

[From psychotherapy to psychoanalysis: Max Levy-Suhl (1876-1947)].

Science.gov (United States)

Hermanns, Ludger M; Schröter, Michael; Stroeken, Harry

2014-01-01

From psychotherapy to psychoanalysis: Max Levy-Suhl (1876-1947). Levy-Suhl can be considered one of the great practising psychotherapists in early 20th century Berlin. He was active in various fields, including ophthalmology, forensic adolescent psychiatry and hypnosis. Prominent among his publications were two handbooks of psychotherapeutic methods. His attitude towards psychoanalysis shifted from initial criticism to acceptance. Ca. 1930 he experienced some kind of conversion, resulting in his training at the Berlin Institute and becoming a member of the German Psychoanalytic Society. As a Jew being forced to emigrate in 1933, Levy-Suhl turned to the Netherlands where he had a psychoanalytic children's home in Amersfoort, followed by an analyst's practice in Amsterdam. He survived the German occupation, but apparently as a broken man. After the war he committed suicide.--The paper is complemented by an appendix, containing documents and an extensive bibliography.

Persistence and extinction for stochastic logistic model with Levy noise and impulsive perturbation

OpenAIRE

Chun Lu; Qiang Ma; Xiaohua Ding

2015-01-01

This article investigates a stochastic logistic model with Levy noise and impulsive perturbation. In the model, the impulsive perturbation and Levy noise are taken into account simultaneously. This model is new and more feasible and more accordance with the actual. The definition of solution to a stochastic differential equation with Levy noise and impulsive perturbation is established. Based on this definition, we show that our model has a unique global positive solut...

Entrevista con Giovanni Levi

Directory of Open Access Journals (Sweden)

Monica Oliveira

2017-06-01

Full Text Available En esta entrevista, Giovanni Levi - como un conocedor del tema de Familia - realiza una importante evaluación sobre el actual estado de las investigaciones realizadas en el Brasil y em el exterior. Con estilo franco, agudo y lucido critica las visiones tradicionales y sus ilusiones ypropone nuevos conceptos y métodos. La historia de la familia debería ceder espacio para el estudio de las redes relacionales o de los mundos relacionales. De la misma forma, la historia cuantitativa debería abrir espacio para el estudio de las cualidades. Ya con relación a la historia de las elites, tan estudiada y reproducida en una diversidad de trabajos, que deberíase mirar en otra perspectiva. Es decir, no mirar a las reglas sociales predeterminadas, sino a los desvíos y a las variaciones. Levi defiende que los historiadores deben trascender a los documentos que se encuentran fácilmente y que pueden fortalecer perspectivas deformadas y esequilibradas de la sociedad. Para él, los historiadores deben esforzarse por estudiar a aquellos grupos que dejaron pocos rastros documentales. En ese esfuerzo existiría una nueva mirada sobre la historia de la familia.

LEVIS ion source and beam characterization on PBFA-II

International Nuclear Information System (INIS)

Renk, T.J.; Tisone, G.C.; Adams, R.G.; Bailey, J.E.; Filuk, A.B.; Johnson, D.J.; Pointon, T.D.

1993-01-01

We report on the continuing development of the LEVIS (Laser Evaporation Ion Source) lithium active ion source for the 15-cm radial focussing ion diode on PBFA-11. We found previously that DC-heating of the anode surface to 150 degrees C maximum for 5 hours resulted in a pure lithium beam. This paper discusses the characterization of LEVIS source uniformity by Faraday cup arrays and multiple lines of sight for visible light spectroscopy. These diagnostics give some evidence of nonuniformity in both A-K gap electric fields and ion current density. Despite this, however, the measured focal spot size appears smaller than with a passive LiF source operated in the same magnetic field topology. Experiments using a curved anode for vertical beam focussing show reduced ion beam turn-on delay by 5 ns by altering the magnetic field topology as well as anode curvature. Another 3--5 ns reduction was achieved by switching from a passive LiF to the active LEVIS source

Overview of levies on energy carriers in Europe

International Nuclear Information System (INIS)

Iten, R.; Gehrig, S.; Koenig, Ch.

2000-01-01

This short report for the Swiss Federal Office of Energy (SFOE) examines the situation with respect to levies and steering taxes on various forms of energy in European countries. Comparisons are made with the situation in Switzerland regarding energy prices for various consumer groups, taxation of energy carriers and exceptions for energy-intensive industries. Details are given on prices of energy and the levies imposed, in particular with respect to carbon taxes. Data are given for 11 European countries and detailed information on regulations concerning exceptions is presented for selected countries. Finally, fuel price differences between neighbouring countries are examined and the role of 'motor-fuel-tourism' is discussed

UK's climate change levy: cost effectiveness, competitiveness and environmental impacts

Energy Technology Data Exchange (ETDEWEB)

Varma, Adarsh [Hull Univ., School of Economic Studies, Hull (United Kingdom)

2003-01-01

This paper intends to examine the cost effectiveness of UK's climate change levy (CCL), its implications on competitiveness of firms and the environmental impact. The paper briefly describes the levy and analyses it under the canons of a good taxation policy. The economic implications of the levy are discussed with theoretical and empirical perspectives. Change in net exports, investment patterns and productivity and inclusion of compliance cost forms the basis for analysing the effect on competitiveness. It discusses the options available to firms to safeguard their competitiveness if it is adversely affected by the CCL. A description of the current scenario of the levy since its inception is also presented. The paper argues the need for a comprehensive policy involving the use of standards, emission trading as well as energy taxes to achieve emission and energy-use reductions. A focal point of this paper is to elucidate the pros and cons of the CCL (energy tax) with respect to an emission trading scheme. (Author)

Levy-Student processes for a stochastic model of beam halos

Energy Technology Data Exchange (ETDEWEB)

Petroni, N. Cufaro [Department of Mathematics, University of Bari, and INFN Sezione di Bari, via E. Orabona 4, 70125 Bari (Italy)]. E-mail: cufaro@ba.infn.it; De Martino, S. [Department of Physics, University of Salerno, and INFN Sezione di Napoli (gruppo di Salerno), Via S. Allende, I-84081 Baronissi (SA) (Italy); De Siena, S. [Department of Physics, University of Salerno, and INFN Sezione di Napoli (gruppo di Salerno), Via S. Allende, I-84081 Baronissi (SA) (Italy); Illuminati, F. [Department of Physics, University of Salerno, and INFN Sezione di Napoli (gruppo di Salerno), Via S. Allende, I-84081 Baronissi (SA) (Italy)

2006-06-01

We describe the transverse beam distribution in particle accelerators within the controlled, stochastic dynamical scheme of the stochastic mechanics which produces time reversal invariant diffusion processes. In this paper we analyze the consequences of introducing the generalized Student laws, namely non-Gaussian, Levy infinitely divisible (but not stable) distributions. We will analyze this idea from two different standpoints: (a) first by supposing that the stationary distribution of our (Wiener powered) stochastic model is a Student distribution; (b) by supposing that our model is based on a (non-Gaussian) Levy process whose increments are Student distributed. In the case (a) the longer tails of the power decay of the Student laws, and in the case (b) the discontinuities of the Levy-Student process can well account for the rare escape of particles from the beam core, and hence for the formation of a halo in intense beams.

Levy-Student processes for a stochastic model of beam halos

International Nuclear Information System (INIS)

Petroni, N. Cufaro; De Martino, S.; De Siena, S.; Illuminati, F.

2006-01-01

We describe the transverse beam distribution in particle accelerators within the controlled, stochastic dynamical scheme of the stochastic mechanics which produces time reversal invariant diffusion processes. In this paper we analyze the consequences of introducing the generalized Student laws, namely non-Gaussian, Levy infinitely divisible (but not stable) distributions. We will analyze this idea from two different standpoints: (a) first by supposing that the stationary distribution of our (Wiener powered) stochastic model is a Student distribution; (b) by supposing that our model is based on a (non-Gaussian) Levy process whose increments are Student distributed. In the case (a) the longer tails of the power decay of the Student laws, and in the case (b) the discontinuities of the Levy-Student process can well account for the rare escape of particles from the beam core, and hence for the formation of a halo in intense beams

Bunker Levy Schemes for Greenhouse Gas (GHG) Emission Reduction in International Shipping

DEFF Research Database (Denmark)

Kosmas, Vasileios; Acciaro, Michele

2017-01-01

, the extent of which depend on the structure of the levy and market conditions. Since there is concern that the costs resulting from the policy will be passed from shipping companies to their customers along the supply chain, the paper dwells on how the costs arising from the enforcement of the levy...

Rotationally invariant family of Levy-like random matrix ensembles

International Nuclear Information System (INIS)

Choi, Jinmyung; Muttalib, K A

2009-01-01

We introduce a family of rotationally invariant random matrix ensembles characterized by a parameter λ. While λ = 1 corresponds to well-known critical ensembles, we show that λ ≠ 1 describes 'Levy-like' ensembles, characterized by power-law eigenvalue densities. For λ > 1 the density is bounded, as in Gaussian ensembles, but λ < 1 describes ensembles characterized by densities with long tails. In particular, the model allows us to evaluate, in terms of a novel family of orthogonal polynomials, the eigenvalue correlations for Levy-like ensembles. These correlations differ qualitatively from those in either the Gaussian or the critical ensembles. (fast track communication)

Basics of Swiss water levy politics - Economic considerations; Grundlagen Wasserzinspolitik. Oekonomische Ueberlegungen - Schlussbericht

Energy Technology Data Exchange (ETDEWEB)

Ott, W.; Staub, C. [econcept AG, Zuerich (Switzerland); Leimbacher, J. [Joerg Leimbacher, Bern (Switzerland)

2008-10-15

This comprehensive final report for the Swiss Federal Office of Energy (SFOE) takes a look at the economic considerations involved in defining the basics for the handling of levies on water commodities. This levy is raised in Switzerland on the use of water and represents the payment made to a commune for the use of its water resources. The report first takes a look at the current situation, the reasons behind the Swiss water levy concept and the reasons why they have to be newly regulated. Changes in market factors are discussed, e.g. the liberalisation of the power market and past and future price developments. Also, the situation on the spot and futures markets for electricity is discussed. The actual production costs for hydropower are discussed and compared with other means of electricity generation. Proposals for readjusting the regulations concerning water levies are discussed.

Campaign Expenditures in School Levy Referenda and Their Relationship to Voter Approval: Evidence from Ohio, 2007-2010

Science.gov (United States)

Ingle, William Kyle; Johnson, Paul Andrew; Givens, Matt Ryan; Rampelt, Jerry

2013-01-01

Using logistic regression, this study sought to understand the relationship between district characteristics, district finances, levy characteristics, and campaign expenditures with new operating levy outcomes. We found that employee benefits as a percentage of the district's budget were negatively associated with levy outcomes, while salaries…

26 CFR 404.6334(d)-1 - Minimum exemption from levy for wages, salary, or other income.

Science.gov (United States)

2010-04-01

... 26 Internal Revenue 18 2010-04-01 2010-04-01 false Minimum exemption from levy for wages, salary... ADMINISTRATION UNDER THE TAX REFORM ACT OF 1976 § 404.6334(d)-1 Minimum exemption from levy for wages, salary, or... him as wages, salary, or other income. Under section 6331(d)(3), a levy upon wages or salary is...

Batik Kreatif Amri Yahya dalam Perspektif Strukturalisme Levi-Strauss

Directory of Open Access Journals (Sweden)

Irfa'ina Rohana Salma

2016-04-01

Full Text Available ABSTRAKPada saat ini sebagaian besar pengembangan motif batik mengacu pada ragam hias tradisional, sehingga hasilnya cenderung monoton. Perlu penyegaran visual dan diversifikasi gagasan untuk menghasilkan motif batik modern yang baru, unik, kreatif, dan inovatif. Tujuan kajian ini adalah menginspirasi para seniman, perajin, desainer untuk menciptakan motif kreatif sebagai diversifikasi produk yang semakin memperkaya khasanah batik Indonesia, dengan mengkaji batik kreatif karya Amri Yahya. Batik kreatif Amri Yahya telah mendapat pengakuan internasional sebagai batik modern. Metode yang digunakan yaitu deskriptif analitis untuk mendeskripsikan dan menganalisis objek seni yaitu batik karya Amri Yahya dengan perspektif Strukturalisme Levi-Strauss. Dari kajian ini dapat disimpulkan bahwa batik kreatif karya Amri Yahya dihasilkan dari keberanian dan kebebasan berekspresi serta konsistensi dalam berkarya seni.Kata kunci: batik, kreatif, Amri Yahya, strukturalisme Levi-StraussABSTRACTAt this time almost all of the batik motive bulk development refers to the traditional decoration, so the results tend to be monotonous. It needs a visual refreshment and diversity idea to produce a modern motive that is new, unique, creative, and innovative. The purpose of this study was to inspire the artists, craft men, designers to create the creative motifs as the diversified products to enrichIndonesian batik, reviewing creative batik of Amri Yahya. These Amri Yahya creative batik hasreceived international recognition as a modern batik. The method used is descriptive analysis todescribe artwork object that is Amri Yahya batik with Levi -Strauss's Structuralism perspective. From this study it can be concluded that the creative work of Amri Yahya batik produced from the encouragement and independecy of expression, as well as consistency in the artwork.Keywords: batik, creative, Amri Yahya, levi - strauss structuralis

Adaptive nonparametric estimation for L\\'evy processes observed at low frequency

OpenAIRE

Kappus, Johanna

2013-01-01

This article deals with adaptive nonparametric estimation for L\\'evy processes observed at low frequency. For general linear functionals of the L\\'evy measure, we construct kernel estimators, provide upper risk bounds and derive rates of convergence under regularity assumptions. Our focus lies on the adaptive choice of the bandwidth, using model selection techniques. We face here a non-standard problem of model selection with unknown variance. A new approach towards this problem is proposed, ...

Comet Shoemaker-Levy 9 meets Jupiter.

Science.gov (United States)

Levy, D. H.; Shoemaker, E. M.; Shoemaker, C. S.

1995-08-01

The impact of comet D/1993 F2 (Shoemaker-Levy 9) with Jupiter was unforgettable, an event probably not to be repeated for millennia to come. One year later the astronomers who first spotted the comet reflect on their discovery, on the anxious months of anticipation before the collision and on what has been learned since.

Persistence and extinction for stochastic logistic model with Levy noise and impulsive perturbation

Directory of Open Access Journals (Sweden)

Chun Lu

2015-09-01

Full Text Available This article investigates a stochastic logistic model with Levy noise and impulsive perturbation. In the model, the impulsive perturbation and Levy noise are taken into account simultaneously. This model is new and more feasible and more accordance with the actual. The definition of solution to a stochastic differential equation with Levy noise and impulsive perturbation is established. Based on this definition, we show that our model has a unique global positive solution and obtains its explicit expression. Sufficient conditions for extinction are established as well as nonpersistence in the mean, weak persistence and stochastic permanence. The threshold between weak persistence and extinction is obtained.

33 CFR 135.103 - Levy and payment of barrel fee on OCS oil.

Science.gov (United States)

2010-07-01

... SECURITY (CONTINUED) MARINE POLLUTION FINANCIAL RESPONSIBILITY AND COMPENSATION OFFSHORE OIL POLLUTION COMPENSATION FUND Levy of Fees § 135.103 Levy and payment of barrel fee on OCS oil. (a) A fee of $.03 per... paragraph (a) of this section applies whenever the unobligated Fund balance is less than $200,000,000. (d...

D'Alembert's paradox, 1900-1914: Levi-Civita and his Italian and French followers

Science.gov (United States)

Tazzioli, Rossana

2017-07-01

Before the First World War, Tullio Levi-Civita (1873-1941) was already a well-known mathematician in Italy and abroad, in particular in France. Professor at the University of Padua since 1898, he had published important contributions to tensor calculus, theory of relativity, differential geometry, hydrodynamics, and the three-body problem. In 1918, when he moved to the University of Rome, he created an international school of mathematics. In this paper, we focus on d'Alembert's paradox to which Levi-Civita and some of his Italian and French followers contributed remarkable solutions. This case-study is used to illustrate Levi-Civita's approach to hydrodynamics and its influence in Italy and France, especially in the period 1910-1914.

Levi-Strauss's "Bricolage" and Theorizing Teachers' Work.

Science.gov (United States)

Hatton, Elizabeth

1989-01-01

A teacher's work is compared to Claude Levi-Strauss's concept of "bricolage." A "bricoleur" is a professional do-it-yourself person, falling somewhere between an odd-job person and a craftsperson. The concept helps to explain pedagogical inadequacy by linking inherent limiting features of teachers' work and some causal…

Kernel-Correlated Levy Field Driven Forward Rate and Application to Derivative Pricing

Energy Technology Data Exchange (ETDEWEB)

Bo Lijun [Xidian University, Department of Mathematics (China); Wang Yongjin [Nankai University, School of Business (China); Yang Xuewei, E-mail: xwyangnk@yahoo.com.cn [Nanjing University, School of Management and Engineering (China)

2013-08-01

We propose a term structure of forward rates driven by a kernel-correlated Levy random field under the HJM framework. The kernel-correlated Levy random field is composed of a kernel-correlated Gaussian random field and a centered Poisson random measure. We shall give a criterion to preclude arbitrage under the risk-neutral pricing measure. As applications, an interest rate derivative with general payoff functional is priced under this pricing measure.

Levy-Student distributions for halos in accelerator beams

International Nuclear Information System (INIS)

Cufaro Petroni, Nicola; De Martino, Salvatore; De Siena, Silvio; Illuminati, Fabrizio

2005-01-01

We describe the transverse beam distribution in particle accelerators within the controlled, stochastic dynamical scheme of stochastic mechanics (SM) which produces time reversal invariant diffusion processes. This leads to a linearized theory summarized in a Schroedinger-like (SL) equation. The space charge effects have been introduced in recent papers by coupling this S-L equation with the Maxwell equations. We analyze the space-charge effects to understand how the dynamics produces the actual beam distributions, and in particular we show how the stationary, self-consistent solutions are related to the (external and space-charge) potentials both when we suppose that the external field is harmonic (constant focusing), and when we a priori prescribe the shape of the stationary solution. We then proceed to discuss a few other ideas by introducing generalized Student distributions, namely, non-Gaussian, Levy infinitely divisible (but not stable) distributions. We will discuss this idea from two different standpoints: (a) first by supposing that the stationary distribution of our (Wiener powered) SM model is a Student distribution; (b) by supposing that our model is based on a (non-Gaussian) Levy process whose increments are Student distributed. We show that in the case (a) the longer tails of the power decay of the Student laws and in the case (b) the discontinuities of the Levy-Student process can well account for the rare escape of particles from the beam core, and hence for the formation of a halo in intense beams

Aviator's Fluid Balance During Military Flight.

Science.gov (United States)

Levkovsky, Anna; Abot-Barkan, Sivan; Chapnik, Leah; Doron, Omer; Levy, Yuval; Heled, Yuval; Gordon, Barak

2018-02-01

A loss of 1% or more of bodyweight due to dehydration has a negative effect on cognitive performance, which could critically affect flight safety. There is no mention in the literature concerning the amounts of military pilots' fluid loss during flight. The aim of this study was to quantify fluid loss of pilots during military flight. There were 48 aviators (mean age 23.9) from the Israeli Air Force who participated in the study, which included 104 training flights in various flight platforms. Bodyweight, urine specific gravity, and environmental heat strain were measured before and after each flight. Fluid loss was calculated as the weight differences before and after the flight. We used a univariate and one-way ANOVA to analyze the effect of different variables on the fluid loss. The mean fluid loss rate was 462 ml · h-1. The results varied among different aircraft platforms and depended on flight duration. Blackhawk pilots lost the highest amount of fluids per flight, albeit had longer flights (mean 108 min compared to 35.5 in fighter jets). Jet fighter pilots had the highest rate of fluid loss per hour of flight (up to 692 ml, extrapolated). Overall, at 11 flights (11%) aircrew completed their flight with a meaningful fluid loss. We conclude that military flights may be associated with significant amount of fluid loss among aircrew.Levkovsky A, Abot-Barkan S, Chapnik L, Doron O, Levy Y, Heled Y, Gordon B. Aviator's fluid balance during military flight. Aerosp Med Hum Perform. 2018; 89(2):9498.

Using nudges to reduce waste? The case of Toronto's plastic bag levy.

Science.gov (United States)

Rivers, Nicholas; Shenstone-Harris, Sarah; Young, Nathan

2017-03-01

The overuse of disposable plastic bags is a major environmental problem across the globe. In recent years, numerous jurisdictions have sought to curb disposable bag use by implementing a levy or fee at the point of purchase. These levies are typically small and symbolic (around $0.05 per bag), but serve as a highly-visible and continuous reminder to consumers. As such, they are consistent with nudging policies that seek to encourage broad changes in behaviour through small, non-coercive measures that influence people's thinking about an issue. While existing empirical evidence suggests that nudges are highly effective in reducing disposable bag use, we argue that many of these studies are flawed because they lack adequate temporal and geographic controls. We use longitudinal data from four waves of a major Canadian survey to analyze the effect of a disposable bag levy in the City of Toronto. Controlling for demographics and changes in social norms over time, we find that the levy increased the use of reusable shopping bags by 3.4 percentage points. Moreover, we find that the impact of the policy was highly variable across behavioural and demographic groups. The levy was highly effective in encouraging people who already used reusable bags to use them more frequently, while having no effect on infrequent users. We also find that the effects are limited to households with high socio-economic status (as measured by income, educational attainment, and housing situation). This suggests important limitations for nudging policy more generally, as people with lower socio-economic status appear to have been unaffected by this behavioural prompt. Copyright © 2016 Elsevier Ltd. All rights reserved.

Can collective searches profit from Levy walk strategies?

Energy Technology Data Exchange (ETDEWEB)

Santos, M C; Da Luz, M G E [Departamento de Fisica, Universidade Federal do Parana, Curitiba-PR, 81531-990 (Brazil); Raposo, E P [Laboratorio de Fisica Teorica e Computacional, Departamento de Fisica, Universidade Federal de Pernambuco, Recife-PE, 50670-901 (Brazil); Viswanathan, G M [Instituto de Fisica, Universidade Federal de Alagoas, Maceio-AL, 57072-970 (Brazil)], E-mail: luz@fisica.ufpr.br

2009-10-30

We address the problem of collective searching in which a group of walkers, guided by a leader, looks for randomly located target sites. In such a process, the necessity to maintain the group aggregated imposes a constraint in the foraging dynamics. We discuss four different models for the system collective behavior, with the leader and followers performing Gaussian as well as truncated Levy walks. In environments with low density of targets we show that Levy foraging is advantageous for the whole group, when compared with Gaussian strategy. Furthermore, certain extra rules must be incorporated in the individuals' dynamics, so that a compromise between the trend to keep the group together and the global efficiency of search is met. The exact character of these rules depends on specific details of the foraging process, such as regeneration of target sites and energy costs.

Major energy users at heart of debate over climate change levy

International Nuclear Information System (INIS)

Anon.

1999-01-01

The UK government's decision to introduce a climate change levy on energy-intensive industry and use the revenues from the levy to cut employers national insurance contributions are discussed. The dispute over energy prices, energy savings potential, industry sectors that have approached the government regarding voluntary agreement concerning energy saving measures and tax relief, the Marshall report examining options for reducing business use of energy, possible exemptions for electricity produced from renewable sources, and the encouragement of businesses to conduct pilot emissions trading schemes are considered. (UK)

Can voter-approved tax levies provide fiscal advantages and stability for local public health agencies?

Science.gov (United States)

Schmalzried, Hans D; Fallon, L Fleming

2013-01-01

Major funding cuts have occurred throughout the United States public health system during the past several years. Funding for local public health agency (LPHA) services and programs is obtained through a patchwork of sources that vary both within and among states. Even though local city and county sources provide a significant proportion of funding for LPHAs, information available in the literature about these revenues is sparse and is not clearly described. This study focused on a single specific revenue stream included in the local sources (local city and county) category: funds voted on directly by the public. The primary purpose of this study was to examine whether this type of funding source provided fiscal advantages for LPHAs. Specifically, we wanted to see how sensitive levy votes were to changing general economic conditions. A questionnaire to collect LPHA levy data was developed, approved, and mailed to county boards of elections in Ohio (n = 88). Elections officials were asked to provide voting results for all LPHA levy ballot attempts since 1994 regardless of outcome. In the study period (1994 through 2011), 250 LPHA property tax levies were placed on election ballots in Ohio. LPHAs were successful in 155 (62.0%) and unsuccessful in 95 (38.0%) attempts. Over the 18-year period, the most noteworthy outcome was a 94.6% pass rate for renewal levies. Our study demonstrated that voter-approved tax levies provide some fiscal advantages for LPHAs: higher per capita revenues than those who have to rely on other sources of income and predictable revenue streams. This translates into more funds being available for public health programs and services. Property tax levies allow citizens to make direct investments in their local health departments.

26 CFR 301.6331-3 - Restrictions on levy while offers to compromise are pending.

Science.gov (United States)

2010-04-01

... are pending. 301.6331-3 Section 301.6331-3 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF... for Collection of Taxes § 301.6331-3 Restrictions on levy while offers to compromise are pending. Cross-reference. For provisions relating to the making of levies while an offer to compromise is pending...

Tax corrections at the external borders of the European Community at the implementation of an energy levy: An inventory

International Nuclear Information System (INIS)

De Wit, G.

1993-09-01

There are several methods to implement an energy levy in the European Union without having a negative impact on the competitive position of energy-intensive industries and businesses in the EU: (1) a worldwide energy levy; (2) partly exemption of energy-intensive industries or businesses in the EU; and (3) an import levy on energy-intensive products from outside the EU, and refunds for industries and businesses in the EU for paid energy levies on products, exported to countries outside the EU. The third option is investigated in this report for two variants: the input variant (levy only on primary energy sources) and the output variant (levies on all the energy-intensive products). Energy-intensive products discussed in this report are energy carriers, food products, paper and board, chemical and synthetic products, ceramic products, and primary products of the metal industry. Attention is paid to the practical execution, the extent to which such a levy can be enforced, and its relation with the GATT. Finally, the advantages and disadvantages of the two variants with tax corrections at the external borders are discussed in relation with the first two options (1) and (2) to guarantee the competitive position of energy-intensive industries and businesses. 4 tabs., 2 appendices, 30 refs

How to Run a Successful School Levy Campaign.

Science.gov (United States)

Meyers, Judith K.

This document describes the public relations strategies employed by the Lakewood (Ohio) City School district to obtain voter support for a school levy. Various aspects of this successful campaign are described, including the formation of administrative committees to oversee campaign activities, steering and citizens' committees, the use of…

The Implementation of Effluent Taxes for Cambodian Industry: An Assessment of Pollutant Levies

OpenAIRE

Sideth Muong

2006-01-01

This study looks at how the Cambodian government might introduce a pollution levy system to address the country's industrial pollution problem. Using information drawn from a variety of sources, including a recent industrial survey, it estimates the levels of pollution charges that would reduce pollution by 25%-85%. It also calculates the overall revenue that such levies would produce and estimates the costs that industry would have to bear in terms of abatement costs and pollution charges. B...

Energy levies and endogenous technology in an empirical simulation model for the Netherlands

International Nuclear Information System (INIS)

Den Butter, F.A.G.; Dellink, R.B.; Hofkes, M.W.

1995-01-01

The belief in beneficial green tax swaps has been particularly prevalent in Europe, where high levels of unemployment and strong preferences for a large public sector (and hence high tax levels) accentuate the desire for revenue-neutral, growth-enhancing reductions in labor income taxes. In this context an empirical simulation model is developed for the Netherlands, especially designed to reckon with the effects of changes in prices on the level and direction of technological progress. It appears that the so-called employment double dividend, i.e. increasing employment and decreasing energy use at the same time, can occur. A general levy yields stronger effects than a levy on household use only. However, the stronger effects of a general levy on employment and energy use are accompanied by shrinking production and, in the longer run, by decreasing disposable income of workers or non-workers. 1 fig., 4 tabs., 1 appendix, 20 refs

Levy-like behaviour in deterministic models of intelligent agents exploring heterogeneous environments

International Nuclear Information System (INIS)

Boyer, D; Miramontes, O; Larralde, H

2009-01-01

Many studies on animal and human movement patterns report the existence of scaling laws and power-law distributions. Whereas a number of random walk models have been proposed to explain observations, in many situations individuals actually rely on mental maps to explore strongly heterogeneous environments. In this work, we study a model of a deterministic walker, visiting sites randomly distributed on the plane and with varying weight or attractiveness. At each step, the walker minimizes a function that depends on the distance to the next unvisited target (cost) and on the weight of that target (gain). If the target weight distribution is a power law, p(k) ∼ k -β , in some range of the exponent β, the foraging medium induces movements that are similar to Levy flights and are characterized by non-trivial exponents. We explore variations of the choice rule in order to test the robustness of the model and argue that the addition of noise has a limited impact on the dynamics in strongly disordered media.

CO2-impacts of a small-scale consumers levy

International Nuclear Information System (INIS)

1995-02-01

Because of a number of developments (altered budgets of Dutch ministries and implementation of environmental policy plans of energy distribution companies in the Netherlands) the 1993 analyses of the effects of a small-scale consumer levy on the emission of CO 2 are updated. First, attention is paid to the conservation impetus as a result of an increase of the energy price for small-scale consumers. Next, the effects that can occur as a consequence of the presently suggested form of the levy (in particular, the exemption of renewable energy and waste heat) are discussed. Subsequently, the alterations of other policy tools, that are necessary in case a higher effectiveness of conservation measures is realized, are dealt with. The direct effect of a higher energy price on the saving behavior of the small-scale consumers is calculated by means of the CENECA-model. 4 tabs., 1 appendix, 8 refs

The paradigm of description in ethnographic translation: the translator Levi-Strauss in Tristes Tropiques

Directory of Open Access Journals (Sweden)

Alice Maria de Araújo Ferreira

2014-11-01

Full Text Available Published in 1955, Tristes Tropiques by Claude Levi-Strauss is an account of the journey that the author and ethnographer made on the American continent, especially in Brazil, in 1930. With a free poetic style not restricted by the austerity of scientific work, Levi-Strauss introduced a reflection that established a crucial rupture in ethnographic studies and in the humanities in general, or rather, the rupture of the gaze. His aim is not precisely the culture of the indigenous people in Brazil, but Levi-Strauss himself as the subject of the gaze. How may one grasp an object that changes as one gazes at it? How does the gaze affect the object while gazing, observing, analyzing, describing, and translating it? Current essay discusses what the translator does to the speech of the other when translating it. Different translation strategies from Portuguese into French proposed by Levi-Strauss in Tristes Tropiques are discussed. Conceiving ethnographic translation from the description paradigm and as an encounter of cultures (but not as replacement, the author analyzes the process performed within the gap between the gaze experience and the production of speech of such gaze to understand the value produced at the end of the axis corresponding to the ethnographic translation-description.

A Study on L-Asparaginase of Nocardia levis MK-VL_113

Directory of Open Access Journals (Sweden)

Alapati Kavitha

2012-01-01

Full Text Available An enzyme-based drug, L-asparaginase, was produced by Nocardia levis MK-VL_113 isolated from laterite soils of Guntur region. Cultural parameters affecting the production of L-asparaginase by the strain were optimized. Maximal yields of L-asparaginase were recorded from 3-day-old culture grown in modified asparagine-glycerol salts broth with initial pH 7.0 at temperature 30∘C. Glycerol (2% and yeast extract (1.5% served as good carbon and nitrogen sources for L-asparaginase production, respectively. Cell-disrupting agents like EDTA slightly enhanced the productivity of L-asparaginase. Ours is the first paper on the production of L-asparaginase by N. levis.

LEVIS lithium ion source experiments on PBFA-II

International Nuclear Information System (INIS)

Renk, T.J.; Tisone, G.C.; Adams, R.G.; Lopez, M.; Clark, B.F.; Schroeder, J.; Bailey, J.E.; Filuk, A.B.; Carlson, A.L.

1992-01-01

PBFA-II is a pulsed power generator designed to apply up to a 25 MV, 20 ns pulse to a focusing 15 cm-radius Applied-B ion diode for inertial confinement fusion applications. Several different approaches have been pursued to produce a high-purity (> 90%), high-current density (5--10 kA/cm 2 ) singly ionized lithium ion source for acceleration in this diode. In addition to having high source purity, such a source should be active, i.e. the ions should be produced before the power pulse arrives, to provide better electrical coupling from the accelerator to the diode. In the LEVIS (Laser EVaporation Ion Source) process, energy from two lasers impinges on a thin (500 nm) lithium or lithium-bearing film on an insulating substrate. The authors will discuss a new series of LEVIS experiments, with a number of improvements: (1) the laser distribution cone was redesigned, resulting in a more uniform illumination of the 4 cm-tall Li-producing surface; (2) the anode surface is being slow-heated to 120--150 C to help drive off contaminants; and (3) they have expanded the number of source and beam diagnostics

The future of levies in a digital environment: final report

NARCIS (Netherlands)

Hugenholtz, P.B.; Guibault, L.; van Geffen, S.

2003-01-01

Copyright levy systems have been premised on the assumption that private copying of protected works cannot be controlled and exploited individually. With the advent of digital rights management (DRM), this assumption must be re-examined. In the digital environment, technical protection measures and

La costruzione de Il sistema periodico di Primo Levi

Directory of Open Access Journals (Sweden)

Martina Bertoldi

2016-11-01

Full Text Available Tra le opere prodotte nel laboratorio del chimico-scrittore Levi quella che meglio rappresenta l'insensatezza della separazione tra letteratura e scienza e la volontà leviana di ricomporre tale frattura è senz'altro Il sistema periodico. Qui infatti, come sostanze chimiche tra loro reagenti, le due discipline partecipano al processo creativo, consentendo allo scrittore la realizzazione di un'opera la cui forma è data dalla successione di una serie di elementi ed il cui contenuto è costituito da un amalgama significativo di spunti autobiografici, storie chimiche ed inserti metaletterari, in un continuo gioco di rinvii tra le due culture. “Costruire”, verbo che accomuna chimica e scrittura, è quanto fa Levi nell'ideare l'architettura del Sistema periodico, che vede rispecchiate nella disposizione dei suoi componenti tematiche costitutive dell'opera stessa, di conseguenza conferendo ai testi un significato che trascende il loro contenuto specifico per risultare dall'analisi dell'ordinamento della raccolta. Un approccio filologico al testo mostra come la particolare conformazione della raccolta sia il risultato di successivi interventi sull'assetto dei testi. In particolare il quadro variantistico ottenuto dal confronto di un gruppo di racconti anticipati su quotidiani o riviste e dei dattiloscritti originali conservati nell'Archivio storico della casa editrice Einaudi con la loro redazione definitiva, testimonia la cura di Levi nel non lasciare alcun racconto irrelato nell'intento di costruire una struttura ordinata e di per se stessa significante, che veicolando elementi tematici offra un ulteriore simbolo di quanto avviene nei testi, sfumando la distinzione tra forma e contenuto. Among Levi’s works, the The Periodic Table is the one which best represents the senselessness of the division between science and literature and the author’s will to achieve a necessary recomposition between the two. Just like chemical substances that react

Aerial Photography and Imagery, Ortho-Corrected - 2008 Digital Orthophotos - Levy County

Data.gov (United States)

NSGIC Education | GIS Inventory — This data set is one component of a digital orthophoto coverage (DOI) over Levy County, FL. This dataset is comprised of 3-band 24-bit (red, green, and blue bands)...

Functional spaces and operators connected with some L\\'evy noises

OpenAIRE

Lytvynov, E.

2006-01-01

We review some recent developments in white noise analysis and quantum probability. We pay a special attention to spaces of test and generalized functionals of some L\\'evy white noises, as well as as to the structure of quantum white noise on these spaces.

Cloning and adoption: a reply to Levy and Lotz.

Science.gov (United States)

Strong, Carson

2008-02-01

In previous articles I discussed the ethics of human reproductive cloning, focusing on a possible future scenario in which reproductive cloning can be accomplished without an elevated risk of anomalies to the children who are created. I argued that in such a scenario it would be ethically permissible for infertile couples to use cloning as a way to have genetically related children and that such use should not be prohibited. In 'Reproductive Cloning and a (Kind of) Genetic Fallacy', Neil Levy and Mianna Lotz raise objections to my conclusions. They disagree with the view, for which I argued, that some couples can have defensible reasons for desiring genetically related children. They also offer several new arguments against reproductive cloning, including an argument that it would diminish the number of adoptions, thereby adversely affecting the welfare of children who need to be adopted. In this paper I point out that Levy and Lotz's criticisms misconstrue my arguments and that there are serious problems with their arguments for prohibiting infertile couples from using cloning, including their argument from adoption.

Levy Stable Processes. From Stationary to Self-Similar Dynamics and Back. An Application to Finance

International Nuclear Information System (INIS)

Burnecki, K.; Weron, A.

2004-01-01

We employ an ergodic theory argument to demonstrate the foundations of ubiquity of Levy stable self-similar processes in physics and present a class of models for anomalous and nonextensive diffusion. A relationship between stationary and self-similar models is clarified. The presented stochastic integral description of all Levy stable processes could provide new insights into the mechanism underlying a range of self-similar natural phenomena. Finally, this effect is illustrated by self-similar approach to financial modelling. (author)

Spazi d’autore. Riscrittura e passaggi di testo ne La strada di Levi

Directory of Open Access Journals (Sweden)

Matteo Martelli

2016-07-01

Full Text Available L’articolo propone un percorso d’analisi sulle strategie di riscrittura e di ripresa di alcuni testi di Primo Levi nel film documentario La strada di Levi e nell’opera parallela La prova. Focalizzandosi sul secondo romanzo di Levi, La tregua, questi lavori evadono dalle consuete pratiche di adattamento, sviluppando forme di riscrittura nelle quali la manipolazione critica delle testualità pregresse è posta in tensione con nuovi testi messi in scena, immagini, video, riorientando la percezione dell’ipotesto entro ulteriori linguaggi. È attraverso tale spazio di circolazione di linguaggi artistici e di pratiche intermediali, che gli autori Davide Ferrario e Marco Belpoliti sembrano poter condurre una riflessione sulle forme culturali dello sguardo e delle odierne pratiche di lettura della realtà (nella sua temporalità e memoria come nella sua spazialità e della sua traduzione attraverso codici semiotici molteplici. In tale spostamento costante del proprio oggetto di riscrittura, La strada di Levi e La prova si mostrano così quali nodi o reti di un processo di lettura dialettico del presente e del passato, in un tentativo di tracciare alcune mappe del mondo contemporaneo.   The essay suggests an analysis of the documentary film La strada di Levi and the correlated work La prova. Focusing on Primo Levi’s book La tregua, these works show a different attitude about adaptation through a constant reorientation of the source text and its juxtaposition with new texts and images, and through a projection of these elements within additional languages. In this way, the authors, Davide Ferrario and Marco Belpoliti, offer an experience of an intermedial artistic practice that involves a reflection on the cultural forms through which the texts interpret the reality (and its temporality or memory and its translation through multiple semiotic codes. The effect of this kind of work is the perception of the documentary film as a network that

Attraction of Sphenophorus levis Vaurie adults (Coleoptera: Curculionidae) to vegetal tissues at different conservation levels; Atracao de adultos de Sphenophorus levis Vaurie (Coleoptera: Curculionidae) a fragmentos vegetais em diferentes estados de conservacao

Energy Technology Data Exchange (ETDEWEB)

Giron-Perez, Katherine; Nakano, Octavio; Silva, Amanda C; Oda-Souza, Melissa [Escola Superior de Agricultura Luiz de Queiroz (ESALQ/USP), Piracicaba, SP (Brazil). Dept. de Entomologia e Acarologia], e-mail: entomologa@ymail.com, e-mail: onakano@esalq.usp.br

2009-07-01

The occurrence of the sugarcane weevil Sphenophorus levis Vaurie is important in sugarcane in some regions in Brazil. Damage is caused by the larvae as they bore into the nodes and can reach 30 ton/ha/year. Many control alternatives have been attempted, but none were satisfactory, except for the use of toxic baits. Therefore, it is necessary to optimize their efficiency or to propose new techniques. The objective of the current study was to evaluate the attractiveness of adults of S. levis to sugarcane nodes and pineapple peelings in an 'Y' tube olfactometer. The sugarcane internodes were treated with 10% molasses, and tested after different periods of fermentation (24, 48 e 72h), at different times of the day (diurnal and nocturnal) and with both sexes. These tests were carried out in order to correlate the response of S. levis to ethyl acetate and ethanol release as a result of the fermentation process. The release of both compounds was monitored by gas chromatography-mass spectrometry (GC-MS). Our data indicated that sugarcane internodes mixed with 10% molasses fermented for 24h and 48h were the most attractive to S. levis (up to 90%). Pineapple peelings attracted 62.5% of the tested insects. The olfactory response was higher during the day, and no differences were found between the sexes. The production of ethanol in all plant substrates was higher than ethyl acetate, but we could not establish a clear correlation with the insect response to baits. (author)

Distribution of the Largest Eigenvalues of the Levi-Smirnov Ensemble

International Nuclear Information System (INIS)

Wieczorek, W.

2004-01-01

We calculate the distribution of the k-th largest eigenvalue in the random matrix Levi - Smirnov Ensemble (LSE), using the spectral dualism between LSE and chiral Gaussian Unitary Ensemble (GUE). Then we reconstruct universal spectral oscillations and we investigate an asymptotic behavior of the spectral distribution. (author)

A betterment levy in Poland and a „fee payable to development” in the Slovak Republic – differences and similarities

Directory of Open Access Journals (Sweden)

Karol Król

2017-06-01

Full Text Available An attempt to compare two public levies calculated by units of territorial government in order to collect resources for infrastructure investments – a betterment levy in Poland and “a fee payable to development” (in Slovak: poplatek za rozvoj in the Slovak Republic was made in the paper. It was assumed that the pursued research objective will be realized by means of the desk research analysis as well as the descriptive and logical one. Legal acts that govern issues of calculating a betterment levy in Poland and also selected legal acts which are obligatory in the Slovak Republic were subject to the detailed analysis. In conclusion, it was revealed that in spite of the fact that both fees are single levies collected for infrastructure investments, their calculating way as well as legal construction are radically different.

Emissions trading and the climate change levy

International Nuclear Information System (INIS)

Connett, Richard

2000-01-01

This paper discusses the flexible mechanisms established in the Kyoto Protocol of the UN Framework on Climate Change focussing on the mechanism whereby countries achieving their target for reducing the emissions of greenhouse gases can trade their excess to countries having difficulty achieving their target. UK measures to meet their commitment, the UK government's proposed climate change levy on the use of energy, negotiated agreements, emissions trading, and the nature, supply and trading of permits are examined. Compatibility with international agreements and the Integrated Pollution Prevention and Control (IPPC) Directive, monitoring, and penalties are considered

27 CFR 70.164 - Surrender of property subject to levy in the case of life insurance and endowment contracts.

Science.gov (United States)

2010-04-01

... the case of life insurance and endowment contracts. (a) In general. This section provides special rules relating to the surrender of property subject to levy in the case of life insurance and endowment... subject to levy in the case of life insurance and endowment contracts. 70.164 Section 70.164 Alcohol...

the priests and the descendants of levi in the book of malachi

African Journals Online (AJOL)

Fanie Snyman for his hospitality and for all his generous efforts to make my stay ... This interpretation of the descendants of Levi has long since found many ...... 1998. Malachi. A New Translation with Introduction and Commentary. New.

Attraction of Sphenophorus levis Vaurie adults (Coleoptera: Curculionidae) to vegetal tissues at different conservation levels

International Nuclear Information System (INIS)

Giron-Perez, Katherine; Nakano, Octavio; Silva, Amanda C; Oda-Souza, Melissa

2009-01-01

The occurrence of the sugarcane weevil Sphenophorus levis Vaurie is important in sugarcane in some regions in Brazil. Damage is caused by the larvae as they bore into the nodes and can reach 30 ton/ha/year. Many control alternatives have been attempted, but none were satisfactory, except for the use of toxic baits. Therefore, it is necessary to optimize their efficiency or to propose new techniques. The objective of the current study was to evaluate the attractiveness of adults of S. levis to sugarcane nodes and pineapple peelings in an 'Y' tube olfactometer. The sugarcane internodes were treated with 10% molasses, and tested after different periods of fermentation (24, 48 e 72h), at different times of the day (diurnal and nocturnal) and with both sexes. These tests were carried out in order to correlate the response of S. levis to ethyl acetate and ethanol release as a result of the fermentation process. The release of both compounds was monitored by gas chromatography-mass spectrometry (GC-MS). Our data indicated that sugarcane internodes mixed with 10% molasses fermented for 24h and 48h were the most attractive to S. levis (up to 90%). Pineapple peelings attracted 62.5% of the tested insects. The olfactory response was higher during the day, and no differences were found between the sexes. The production of ethanol in all plant substrates was higher than ethyl acetate, but we could not establish a clear correlation with the insect response to baits. (author)

Estimating Resource Costs of Levy Campaigns in Five Ohio School Districts

Science.gov (United States)

Ingle, W. Kyle; Petroff, Ruth Ann; Johnson, Paul A.

2011-01-01

Using Levin and McEwan's (2001) "ingredients method," this study identified the major activities and associated costs of school levy campaigns in five districts. The ingredients were divided into one of five cost categories--human resources, facilities, fees, marketing, and supplies. As to overall costs of the campaigns, estimates ranged…

The Electricity Feed Law levy - how reliably can it be predicted?; Wie verlaesslich laesst sich die EEG-Umlage prognostizieren?

Energy Technology Data Exchange (ETDEWEB)

Bause, Rainer; Schulz, Woldemar [Amprion GmbH, Dortmund (Germany); Buehler, Holger [EnBW TNG, Stuttgart (Germany); Hodurek, Claus [50Hertz Transmission GmbH, Berlin (Germany); Kiessling, Axel [TenneT TSO GmbH, Bayreuth (Germany)

2011-10-15

By paying their monthly electricity bill German consumers are promoting the transition to tomorrow's resource-efficient electricity supply system, in which the largest part of electricity used is to come from renewable energy resources. Every year Germany's transmission system operators publish what is referred to as the ''EEG-Umlage'' (report on the Electricity Feed Law levy, or EEG levy), which shows how much every German household will be paying for the promotion of renewable energies in the coming year. The determination of the EEG levy involves uncertainties and imponderabilities which have to be taken into account in its calculation. The crucial task is to find a suitable systematic scheme for predicting the renewable energy yield.

Linguagem e tradição em Carlo Levi: marcas do arcaico no sul italiano

Directory of Open Access Journals (Sweden)

Amarilis Gallo Coelho

2011-10-01

Full Text Available Carlo Levi, escritor italiano que objetiva documentar as peculiaridades e a diversidade social de seu país, utiliza, além do léxico colorido constante em sua obra, outros artifícios de expressão, tais como o emprego de formas-símbolo, como pedra, e amostras de linguagem, que caracterizam não só o plurilinguismo italiano, mas também a manutenção do arcaico e da história, através dos hábitos lingüísticos e sociais. Pelo uso estilístico e a constatação real de formas greco-latinas, assim como seus reflexos nos dialetos locais, Levi retrata com autenticidade o apego à tradição e a imobilidade espaço-temporal do homem meridional italiano.Carlo Levi raggiunge, nel contatto amoroso con le immagini ed i suoni meridionali, il passato arcaico presente, “dipinto” con spontaneità e autenticità, attraverso la gente, le cose e le voci di quello che lui chiama affettuosamente “mia terra” e miei “contadini”.

Subordinated Levy Processes and Applications to Crude Oil Options

OpenAIRE

Noureddine Krichene

2005-01-01

One approach to oil markets is to treat oil as an asset, besides its role as a commodity. Speculative and nonspeculative activity by investors in the derivatives markets could be responsible for a sizable increase in oil prices. This paper recognizes both the consumption and investment aspects of crude oil and proposes Levy processes for modeling uncertainty and options pricing. Calibration to crude oil futures' options shows high volatility of oil futures prices, fat-tailed, and right-skewed...

BALTIMORE’S M.S. LEVY AND SONS: Straw Hat Makers to the World, 1870-1960

Directory of Open Access Journals (Sweden)

Jessica I. Elfenbein

2008-01-01

Full Text Available From 1860 to 1960, Baltimore was an important center of the men’s ready-to- wear clothing industries. German-speaking Jews created many businesses that manufactured and sold underwear, men’s suits, and specialty items like hats and umbrellas. The straw hat making firm started by M.S. Levy is an interesting example of a Baltimore-based, family-owned niche business that existedfor 90 years, through three generations ofa singlefamily. The M.S. Levy and Sons story has two main chapters. The first covers the period from its founding by Michael Simon Levy in the 1870s through his son Julius’ death in 1926. This is the story of ascension. A premonition about the coming popularity of straw hats, together with a small but important technological breakthrough, positioned a family and a small industry for significant expansion. The second period began in 1930 with the introduction of wool felt hats and the death of William, M.S. Levy’s oldest son, and includes the Great Depression, unionization, merger, third generation leadership, and finally, in 1959, the family’s withdrawal from the industry. This later period, as told by grandsons of the founder, is the story of struggle followed by decline.

Primo Levi and Ivan Denisovič: The Literary Act between Representation and Expressive Capacity

Directory of Open Access Journals (Sweden)

Pietro Tosco

2011-11-01

Full Text Available Se questo è un uomo di Primo Levi e Una giornata di Ivan Denisovič di Aleksandr Solženicyn sono due “atti letterari” che hanno contribuito in modo significativo alla conoscenza storica del XX secolo: il primo nell’Occidente dei campi di concentramento nazisti, il secondo nell’Oriente del Gulag. Perché sono così famosi? C’è qualcosa che li accomuna? Questo saggio si propone di analizzare la forza della letteratura come luogo di conoscenza e autocoscienza. Se le opere di Levi e Solženicyn hanno un grande valore come testimonianze, in esse la forza della testimonianza è data dal “gesto letterario” che le ha create, un gesto che produce una conoscenza sintetica in cui gli universali esistono solo nel particolare.

Tight Error Bounds for Fourier Methods for Option Pricing for Exponential Levy Processes

KAUST Repository

Crocce, Fabian; Hä ppö lä , Juho; Keissling, Jonas; Tempone, Raul

2016-01-01

for the discontinuities in the asset price. The Levy -Khintchine formula provides an explicit representation of the characteristic function of a L´evy process (cf, [6]): One can derive an exact expression for the Fourier transform of the solution of the relevant PIDE

Prevention before profits: a levy on food and alcohol advertising.

Science.gov (United States)

Harper, Todd A; Mooney, Gavin

2010-04-05

The recent interest in health promotion and disease prevention has drawn attention to the role of the alcohol and junk-food industries. Companies supplying, producing, advertising or selling alcohol or junk food (ie, foods with a high content of fat, sugar or salt) do so to generate profits. Even companies marketing "low-carbohydrate" beers, "mild" cigarettes, or "high-fibre" sugary cereals are not primarily concerned about population health, more so increased sales and profits. In a competitive market, it is assumed that consumers make fully informed choices about costs and benefits before purchasing. However, consumers are not being fully informed of the implications of their junk-food and alcohol choices, as advertising of these products carries little information on the health consequences of consumption. We propose that there should be a levy on advertising expenditure for junk food and alcoholic beverages to provide an incentive for industry to promote healthier products. Proceeds of the levy could be used to provide consumers with more complete and balanced information on the healthy and harmful impacts of food and alcohol choices. Our proposal addresses two of the greatest challenges facing Australia's preventable disease epidemic - the imbalance between the promotion of healthier and unhealthy products, and securing funds to empower consumer choice.

Cuckoo search via Levy flights applied to uncapacitated facility location problem

Science.gov (United States)

Mesa, Armacheska; Castromayor, Kris; Garillos-Manliguez, Cinmayii; Calag, Vicente

2017-11-01

Facility location problem (FLP) is a mathematical way to optimally locate facilities within a set of candidates to satisfy the requirements of a given set of clients. This study addressed the uncapacitated FLP as it assures that the capacity of every selected facility is finite. Thus, even if the demand is not known, which often is the case, in reality, organizations may still be able to take strategic decisions such as locating the facilities. There are different approaches relevant to the uncapacitated FLP. Here, the cuckoo search via Lévy flight (CS-LF) was used to solve the problem. Though hybrid methods produce better results, this study employed CS-LF to determine first its potential in finding solutions for the problem, particularly when applied to a real-world problem. The method was applied to the data set obtained from a department store in Davao City, Philippines. Results showed that applying CS-LF yielded better facility locations compared to particle swarm optimization and other existing algorithms. Although these results showed that CS-LF is a promising method to solve this particular problem, further studies on other FLP are recommended to establish a strong foundation of the capability of CS-LF in solving FLP.

Primo Levi and the Periodic Table: Teaching Chemistry Using A Literary Text (Excerpt)

Science.gov (United States)

Osorio, Viktoria Klara Lakatos; Tiedemann, Peter Wilhelm; Porto, Paulo Alves

2007-01-01

The excerpts from The Periodic Table book written by Primo Levi is discussed related to chemical concepts. The use of a literary text as a starting point of discussions of chemical concepts has allowed the integration of various topics covered in separate courses of the undergraduate program in chemistry.

LEVIS active anode lithium ion source development on PBFA-II

International Nuclear Information System (INIS)

Renk, T.J.; Tisone, G.C.; Adams, R.G.; Clark, B.F.; Reyes, C.; Bailey, J.E.; Filuk, A.B.; Desjarlais, M.P.; Johnson, D.J.; Carlson, A.L.; Lake, P.

1993-01-01

Experiments are ongoing on the PBFA-II Accelerator (10 MV typical, 50 ns) to optimize an active lithium ion source in a 15-cm focusing Applied-B ion diode using the LEVIS (Laser Evaporation Ion Source) process. Two laser pulses impinge on a thin (500 nm) Li or Li-bearing alloy on an insulating substrate. A Nd:YAG laser beam (1 μm, 8 ns, 0.1--0.2 J/cm 2 ) creates a thin (∼1 mm) Li vapor, which is then ionized by a 30--60 mJ/cm 2 dye laser tuned to the first resonant transition of Li (670.8 nm). In order to achieve a high-purity Li beam on PBFA-II with LEVIS, it has proven necessary to clean the anode surface in some way. The principal technique has been DC-heating of the anode to temperatures of 150--200 C for typically 5 hours, and for as long as 13 hours, prior to machine firing. Use of a LiAg alloy and YAG energy densities of 200 mJ/cm 2 have yielded beams of Li purity greater than 90%. They authors also plan to test a diode configuration that deposits Li in-situ on the anode surface just prior to the machine shot, as an alternative to DC-heating

Efficient Option Pricing under Levy Processes, with CVA and FVA

Directory of Open Access Journals (Sweden)

Jimmy eLaw

2015-07-01

Full Text Available We generalize the Piterbarg (2010 model to include 1 bilateral default risk as in Burgard and Kjaer (2012, and 2 jumps in the dynamics of the underlying asset using general classes of L'evy processes of exponential type. We develop an efficient explicit-implicit scheme for European options and barrier options taking CVA-FVA into account. We highlight the importance of this work in the context of trading, pricing and management a derivative portfolio given the trajectory of regulations.

Alternatives to the EEG levy. Possible effects of a reform of the energy transition financing on the industry

International Nuclear Information System (INIS)

Scheyhing, Joerg

2017-01-01

Although it has been adjusted six times since the year 2000, it has not yet been possible to manage the unrestricted growth of the EEG levy. In the 2017 election year, it becomes therefore ever more obvious that an alternative way to finance the energy transition is high on the political agenda. This would lead to significant changes for energy-intensive companies, regardless of whether they have benefited from a release from the levy or not. At the same time, the alternatives currently discussed have quite different effects on the industrial companies concerned and thereby the industry location Germany. [de

Simulation-based computation of the workload correlation function in a Levy-driven queue

NARCIS (Netherlands)

P. Glynn; M.R.H. Mandjes (Michel)

2009-01-01

htmlabstractIn this paper we consider a single-server queue with Levy input, and in particular its workload process (Q_t), focusing on its correlation structure. With the correlation function defined as r(t) := Cov(Q_0, Q_t)/Var Q_0 (assuming the workload process is in stationarity at time 0), we

Self-similar anomalous diffusion and Levy-stable laws

International Nuclear Information System (INIS)

Uchaikin, Vladimir V

2003-01-01

Stochastic principles for constructing the process of anomalous diffusion are considered, and corresponding models of random processes are reviewed. The self-similarity and the independent-increments principles are used to extend the notion of diffusion process to the class of Levy-stable processes. Replacing the independent-increments principle with the renewal principle allows us to take the next step in generalizing the notion of diffusion, which results in fractional-order partial space-time differential equations of diffusion. Fundamental solutions to these equations are represented in terms of stable laws, and their relationship to the fractality and memory of the medium is discussed. A new class of distributions, called fractional stable distributions, is introduced. (reviews of topical problems)

Geertz versus Levi-Strauss: latent structural dispositions in Geertz "theory of culture"?

Directory of Open Access Journals (Sweden)

Gordana Gorunović

2016-02-01

Full Text Available These are two authors, in Foucauldian terms that certainly belong to the most influential individuals in socio-cultural anthropology, as well as in the social sciences and interdisciplinary research more broadly. Claude Levi- Strauss became some kind of an "intellectual hero" during the domination of structuralism in the mid-twentieth century and during the 1960s, while Clifford Geertz was an ‘icon and ambassador’ of anthropology in the second half of the twentieth century. They are both one of the founders of the discourse theory. They not only established a distinct theoretical approaches and methods – structural (Levi-Strauss and interpretative anthropology (Clifford Geertz, but through their intellectual authority they also inspired paradigms and intellectual movements making structuralism and "interpretation of culture" more than some passing episodes in the history of social though (in terms of "trendy ideas". My aim is to make some parallels between these two authors, who despite all the differences that are evident in their epistemological discourses, theoretical approaches and methods (as well as in their ethnographic and anthropological writings itself still have some similarities in their theorisation and interpretation of culture, which I would like to stress in this paper.

Periodic Comet Shoemaker-Levy 9 Collides with Jupiter. Background Material for Science Teachers.

Science.gov (United States)

Jet Propulsion Lab., Pasadena, CA.

In July of 1994, fragments of Comet Shoemaker-Levy collided with Jupiter. This document has been provided to better inform students of the work that will be done by scientists and others involved in the study of this event. This document offers some background material on Jupiter, comets, what has and possibly will happen, and how scientists…

Fairer flying: an international air travel levy for adaptation

Energy Technology Data Exchange (ETDEWEB)

Chambwera, Muyeye; Muller, Benito

2008-11-15

For the world's poorest countries and communities, adaptation to climate change is urgently needed, but costly: estimates run into tens of billions of dollars a year. Given the shortfall in current international adaptation funding, how can resources for the developing world be raised? An adaptation levy on international air travel could help fill the gap. A small per-trip payment by passengers could contribute US$8 billion to US$10 billion a year towards adaptation. Similar schemes in France and elsewhere show that this kind of ethical solidarity and 'polluter pays' approach would be simple to implement in practical and institutional terms.

Fractal diffusion equations: Microscopic models with anomalous diffusion and its generalizations

International Nuclear Information System (INIS)

Arkhincheev, V.E.

2001-04-01

To describe the ''anomalous'' diffusion the generalized diffusion equations of fractal order are deduced from microscopic models with anomalous diffusion as Comb model and Levy flights. It is shown that two types of equations are possible: with fractional temporal and fractional spatial derivatives. The solutions of these equations are obtained and the physical sense of these fractional equations is discussed. The relation between diffusion and conductivity is studied and the well-known Einstein relation is generalized for the anomalous diffusion case. It is shown that for Levy flight diffusion the Ohm's law is not applied and the current depends on electric field in a nonlinear way due to the anomalous character of Levy flights. The results of numerical simulations, which confirmed this conclusion, are also presented. (author)

New levy on nitrogen oxide emissions: First 'refundable' pollution charge

International Nuclear Information System (INIS)

Andersson, Sus; Hanneberg, P.

1991-01-01

A new law imposing a charge on nitrogen oxide emissions from combustion installations will soon be coming into force in Sweden. The money generated by the charge will not stay in the exchequer, however, but will be repaid to the plants concerned in proportion to the amount of useful energy they produce. This will be the first environment levy in Sweden to be based on measurements of actual emissions. Emissions of sulphur and carbon dioxide are already taxed. These taxes, unlike other environmental charges, not only have an incentive function, but are also a source of income for the state

Decrease of energy and emission prices undesired. Unfair attack on CO2-levies

International Nuclear Information System (INIS)

Blom, M.; De Keizer, I.; Benner, J.

2005-01-01

Recently, in the Netherlands, fuel taxes and prices for CO2 emission are criticised. High energy prices are used to suggest other forms of pricing regulations. However, the higher energy prices and CO2-levies are very useful in realizing a sustainable energy supply. More transparency in the market for emissions trading is required to prevent unfair on-charge expenses of CO2-charges [nl

Optical design of the comet Shoemaker-Levy speckle camera

Energy Technology Data Exchange (ETDEWEB)

Bissinger, H. [Lawrence Livermore National Lab., CA (United States)

1994-11-15

An optical design is presented in which the Lick 3 meter telescope and a bare CCD speckle camera system was used to image the collision sites of the Shoemaker-Levy 9 comet with the Planet Jupiter. The brief overview includes of the optical constraints and system layout. The choice of a Risley prism combination to compensate for the time dependent atmospheric chromatic changes are described. Plate scale and signal-to-noise ratio curves resulting from imaging reference stars are compared with theory. Comparisons between un-corrected and reconstructed images of Jupiter`s impact sites. The results confirm that speckle imaging techniques can be used over an extended time period to provide a method to image large extended objects.

Levy-taxis: a novel search strategy for finding odor plumes in turbulent flow-dominated environments

International Nuclear Information System (INIS)

Pasternak, Zohar; Grasso, Frank W; Bartumeus, Frederic

2009-01-01

Locating chemical plumes in aquatic or terrestrial environments is important for many economic, conservation, security and health related human activities. The localization process is composed mainly of two phases: finding the chemical plume and then tracking it to its source. Plume tracking has been the subject of considerable study whereas plume finding has received little attention. We address here the latter issue, where the searching agent must find the plume in a region often many times larger than the plume and devoid of the relevant chemical cues. The probability of detecting the plume not only depends on the movements of the searching agent but also on the fluid mechanical regime, shaping plume intermittency in space and time; this is a basic, general problem when exploring for ephemeral resources (e.g. moving and/or concealing targets). Here we present a bio-inspired search strategy named Levy-taxis that, under certain conditions, located odor plumes significantly faster and with a better success rate than other search strategies such as Levy walks (LW), correlated random walks (CRW) and systematic zig-zag. These results are based on computer simulations which contain, for the first time ever, digitalized real-world water flow and chemical plume instead of their theoretical model approximations. Combining elements of LW and CRW, Levy-taxis is particularly efficient for searching in flow-dominated environments: it adaptively controls the stochastic search pattern using environmental information (i.e. flow) that is available throughout the course of the search and shows correlation with the source providing the cues. This strategy finds natural application in real-world search missions, both by humans and autonomous robots, since it accommodates the stochastic nature of chemical mixing in turbulent flows. In addition, it may prove useful in the field of behavioral ecology, explaining and predicting the movement patterns of various animals searching for food

Levy-taxis: a novel search strategy for finding odor plumes in turbulent flow-dominated environments

Energy Technology Data Exchange (ETDEWEB)

Pasternak, Zohar; Grasso, Frank W [BioMimetic and Cognitive Robotics Laboratory, Department of Psychology, Brooklyn College, The City University of New York, 2900 Bedford Avenue, Brooklyn 11210, NY (United States); Bartumeus, Frederic [Department of Ecology and Evolutionary Biology and Princeton Environmental Institute, 106 Guyot Hall, Princeton University, Princeton 08544, NJ (United States)], E-mail: zpast@yahoo.com

2009-10-30

Locating chemical plumes in aquatic or terrestrial environments is important for many economic, conservation, security and health related human activities. The localization process is composed mainly of two phases: finding the chemical plume and then tracking it to its source. Plume tracking has been the subject of considerable study whereas plume finding has received little attention. We address here the latter issue, where the searching agent must find the plume in a region often many times larger than the plume and devoid of the relevant chemical cues. The probability of detecting the plume not only depends on the movements of the searching agent but also on the fluid mechanical regime, shaping plume intermittency in space and time; this is a basic, general problem when exploring for ephemeral resources (e.g. moving and/or concealing targets). Here we present a bio-inspired search strategy named Levy-taxis that, under certain conditions, located odor plumes significantly faster and with a better success rate than other search strategies such as Levy walks (LW), correlated random walks (CRW) and systematic zig-zag. These results are based on computer simulations which contain, for the first time ever, digitalized real-world water flow and chemical plume instead of their theoretical model approximations. Combining elements of LW and CRW, Levy-taxis is particularly efficient for searching in flow-dominated environments: it adaptively controls the stochastic search pattern using environmental information (i.e. flow) that is available throughout the course of the search and shows correlation with the source providing the cues. This strategy finds natural application in real-world search missions, both by humans and autonomous robots, since it accommodates the stochastic nature of chemical mixing in turbulent flows. In addition, it may prove useful in the field of behavioral ecology, explaining and predicting the movement patterns of various animals searching for food

Levy flights and self-similar exploratory behaviour of termite workers: beyond model fitting.

Directory of Open Access Journals (Sweden)

Octavio Miramontes

Full Text Available Animal movements have been related to optimal foraging strategies where self-similar trajectories are central. Most of the experimental studies done so far have focused mainly on fitting statistical models to data in order to test for movement patterns described by power-laws. Here we show by analyzing over half a million movement displacements that isolated termite workers actually exhibit a range of very interesting dynamical properties--including Lévy flights--in their exploratory behaviour. Going beyond the current trend of statistical model fitting alone, our study analyses anomalous diffusion and structure functions to estimate values of the scaling exponents describing displacement statistics. We evince the fractal nature of the movement patterns and show how the scaling exponents describing termite space exploration intriguingly comply with mathematical relations found in the physics of transport phenomena. By doing this, we rescue a rich variety of physical and biological phenomenology that can be potentially important and meaningful for the study of complex animal behavior and, in particular, for the study of how patterns of exploratory behaviour of individual social insects may impact not only their feeding demands but also nestmate encounter patterns and, hence, their dynamics at the social scale.

In regard to Levi-Strauss’s "motive of oblivion". Structure of disturbed communication and styles of thoughts in transitory Serbia

Directory of Open Access Journals (Sweden)

Dragana Antonijević

2016-02-01

Full Text Available This paper starts with Levi-Strauss’s semantic concept that consists of oblivion, misunderstanding, indiscretion and nostalgia. Through his analysis of North American and Greek myths, Levi-Strauss concluded that "semantic filed of oblivion" has an important meaning especially in the construction of particular rules and rituals; or, in other words, it has an important part in the introduction of culture to the nature of cognitive and social processes. After the introduction of concept Structure of disturbed communication and some corrections to the Levi-Strauss’s concept, I start with the proposition that the period of transition represents unstable and ‘slippery’ time in which society negotiates different meanings. That is the time when different styles of thoughts, represented by different and powerful groups that have an impact on current social, political and ideological processes, compete with each other fighting for supremacy. Their field of communication can be seen as a field of "disturbed communication", which in the final instance has a normative function: to reinforce and regulate certain attitudes, ideas and knowledge. This is achieved through the narratives which symbolise a community of newly established order in the moment of its supposed sociohistorical stabilisation. Finally, combining two different theoretical models – Levi-Strauss’s one described above with Greimas’s ideas about structures of modes of veridiction, this paper predicts chances of particular paradigmatic forms of thought in transitory Serbia to became dominant modes of thought, despite of their current low visibility in the public sphere. In mythical terms, it seems though that their domineering efforts are predetermined to success or fail, since they position themselves according to the laws immanent to these structures themselves, which on their part a priori position these structures as powerful orpowerless, influential or non

26 CFR 301.6331-4 - Restrictions on levy while installment agreements are pending or in effect.

Science.gov (United States)

2010-04-01

... agreements are pending or in effect. 301.6331-4 Section 301.6331-4 Internal Revenue INTERNAL REVENUE SERVICE... Property for Collection of Taxes § 301.6331-4 Restrictions on levy while installment agreements are pending... is pending with the Internal Revenue Service (IRS), for 30 days immediately following the rejection...

A Review of the Case of a Levy-Grant Scheme (LGS) in the UK Construction Industry

Science.gov (United States)

Abdel-Wahab, Mohamed; Dainty, Andrew; Ison, Stephen

2010-01-01

A Levy-Grant Scheme (LGS) has existed in the UK construction industry since 1964 to provide financial support for companies undertaking training activities. Despite the support of the LGS for various training activities, notably apprenticeships, the construction industry continues to suffer from both labour shortages and an under-investment in…

Asymptotics for Exponential Levy Processes and their Volatility Smile: Survey and New Results

OpenAIRE

Leif Andersen; Alexander Lipton

2012-01-01

Exponential L\\'evy processes can be used to model the evolution of various financial variables such as FX rates, stock prices, etc. Considerable efforts have been devoted to pricing derivatives written on underliers governed by such processes, and the corresponding implied volatility surfaces have been analyzed in some detail. In the non-asymptotic regimes, option prices are described by the Lewis-Lipton formula which allows one to represent them as Fourier integrals; the prices can be trivia...

The UK's Levy Control Framework for renewable electricity support: Effects and significance

International Nuclear Information System (INIS)

Lockwood, Matthew

2016-01-01

There is a long-standing debate over price vs. quantity approaches to supporting the deployment of renewable electricity technologies. In the context of a recent shift from quantity to price-based support, the UK has also introduced a new form of budgetary framework, the Levy Control Framework (LCF). The introduction of the LCF has been very important for investors but has received relatively little attention in the academic literature. The paper gives an overview of the LCF, explores its effects on renewables policy, on consumers and on investor confidence arguing that an unintended consequence of its introduction has been to increase uncertainty, through interactions with underlying support mechanisms. A number of problems with the current scope and design of the LCF are noted. It is argued that the LCF is best understood as aimed at avoiding a political backlash against renewable support policy in a context where the benefits of such policy are concentrated economically and socially. The paper concludes by placing the LCF within a wider context of a shift towards greater budgetary control over renewable energy support policy across European countries. - Highlights: • Gives an description of the Levy Control Framework. • Analyses the effects of the LCF on UK renewable policy. • Reviews possible purposes of the LCF. • Evaluates the effects of the LCF on consumers and investors. • Places the LCF in context of greater cost control over renewables across the EU.

Valuation of exotic options in the framework of Levy processes

Energy Technology Data Exchange (ETDEWEB)

Milev, Mariyan, E-mail: marianmilev2002@gmail.com; Georgieva, Svetla, E-mail: marianmilev2002@gmail.com; Markovska, Veneta, E-mail: marianmilev2002@gmail.com [Department of Mathematics and Physics, UFT-Plovdiv, bul. Maritza 26, 4002 Plovdiv (Bulgaria)

2013-12-18

In this paper we explore a straightforward procedure to price derivatives by using the Monte Carlo approach when the underlying process is a jump-diffusion. We have compared the Black-Scholes model with one of its extensions that is the Merton model. The latter model is better in capturing the market’s phenomena and is comparative to stochastic volatility models in terms of pricing accuracy. We have presented simulations of asset paths and pricing of barrier options for both Geometric Brownian motion and exponential Levy processes as it is the concrete case of the Merton model. A desired level of accuracy is obtained with simple computer operations in MATLAB for efficient computational time.

76 FR 11522 - In the Matter of Progress Energy Florida, Inc. (Combined License Application, Levy County Nuclear...

Science.gov (United States)

2011-03-02

... NUCLEAR REGULATORY COMMISSION [Docket Nos. 52-029-COL, 52-030-COL] In the Matter of Progress Energy Florida, Inc. (Combined License Application, Levy County Nuclear Power Plant, Units 1 and 2... by the Nuclear Regulatory Commission staff in this case. Mr. Dehmel has not previously performed any...

"Hired Guns" and "Legitimate Voices": The Politics and Participants of Levy Campaigns in Five Ohio School Districts

Science.gov (United States)

Ingle, William Kyle; Johnson, Paul Andrew; Petroff, Ruth Ann

2012-01-01

Background: In Ohio, levy campaigns are a burdensome task for district administrators and stakeholders alike. To date, there is little research on the districts' role in crafting school budget referenda campaigns. Purpose: This study asked three research questions: How did the macropolitical contexts shape stakeholders' decision making in terms of…

Study on the effects of the regulating energy levy for businesses. State of the art at the end of 1997

International Nuclear Information System (INIS)

Bode, J.W.; Worrell, E.; Berkhout, P.H.G.; Giesberger, D.; Paape, A.H.; Velthuijsen, J.W.

1998-05-01

January 1, 1996, the so-called regulating energy levy (REB, abbreviated in Dutch and also known as ecotax or small-scale consumer levy ('kleinverbruikersheffing')) came into effect in the Netherlands. The Second chamber of the Dutch parliament requested an annual report of the effects of the REB. A first report was published in the summer of 1997. It appeared that for subsequent years a more elaborated survey is needed for which more research is required. In this report the results of a study on the role of the REB on energy conservation investment decisions, taken in several businesses (retail trade, the hotel and restaurant sector (horeca in Dutch), offices in the services sector, small businesses in the metals industry, and installers of energy saving installations),are presented 31 refs

The Disruption and Demise of Periodic Comet Shoemaker-Levy 9

Science.gov (United States)

Asphaug, Erik; Benz, Willy; Cuzzi, Jeffrey (Technical Monitor)

1994-01-01

The impact of the fragmented comet Shoemaker-Levy 9 (SL9) into Jupiter this July promises to change our understanding of the outer solar system. More than twenty mountain-sized conglomerates of ice and rock will hit the atmosphere at approx. 50 km/s over the course of a week beginning July 16, releasing approx. 10(exp 4) to 10(exp8) megatons of energy per burst, and providing unique and perhaps pivotal clues to the properties of comets and the physics of massive atmospheres. Because the fragments will strike the far side of Jupiter, data acquisition, analysis and interpretation will be quite sensitive to the actual size and energy of the fragments. We therefore examine an event which took place two summers ago, unnoticed and unobserved: the disruption of SL9 into a "string of pearls' as it passed within the Roche limit at perijove. We first demonstrate, on the basis of timescales of tidal interaction, that the comet could not have broken into 20+ fragments through a hierarchy of brittle fracture events. Next, noting that the tidal stress was too weak to have even fragmented an uncompressed mass of freshly fallen snow, we run models for a strengthless comet held together only by self-gravity. We explore the initial size, density, and rotation. We conclude that a 4 km diameter comet (smaller if a prograde rotator) of density approx. 0.5 g/cu cm disrupts and disperses into a chain of fragments similar to Shoemaker-Levy 9, whether we begin with 21, 85, 169, 700 or 2000 sub-grains. Gravitational reaccumulation is evidently the answer, and there is no need to invoke the presence of 21 "cometesimals" as the subscale of the comet. To explain how a comet can be weaker than uncompacted snow, we show that the ring-plane crossing prior to perijove could have caused total damage. Finally, we compute the tidal stress on impactors as they approach Jupiter this July. Objects of various density are moderately distorted but not disrupted by the time they strike the planet.

A Mortificação do Corpo em É Isto Um Homem?, de Primo Levi

Directory of Open Access Journals (Sweden)

José Carlos Felix

2015-10-01

Full Text Available http://dx.doi.org/10.5007/2175-8026.2015v68n3p43 Dentre os incontáveis testemunhos e narrativas que se propuseram denunciar, narrar e dar sentido à experiência produzida pela Shoah, o livro É isto um homem?, do escritor italiano Primo Levi, prefigura como um dos relatos mais contundentes acerca dos horrores e monstruosidades vividas nos campos de concentração nazistas durante a Segunda Guerra Mundial. O presente artigo propõe uma discussão acerca das formas de violência e mortificação do corpo apontadas no relato de Levi, as quais revelam um processo de reificação da vida, cujas consequências mais diretas afetam tanto a relação do indivíduo com seu próprio corpo quanto com o do outrem. Para tanto, partiremos do testemunho do autor acerca do processo de reificação e degradação humana, bem como das reflexões sobre a relação entre esclarecimento e barbárie pensadas por Horkheimer e Adorno e dos conceitos de soberania e biopolitização do estado chamada de “vida nua” de Agamben.

Levi-Strauss Ve Roland Barthes’ın Yaklaşımıyla “God Of War III” Oyununun Mitsel Çözümlemesi

OpenAIRE

SEPETÇİ, Tülin

2016-01-01

Bu çalışmanın amacı, Roland Barthes ve Levi-Strauss’un mit kuramlarını bir popüler kültür ürünü olarak ele alınan “God of War III” adlı video oyunu bağlamında karşılaştırmaktır. Çalışmada öncelikle tarihsel süreç içerisinde mitlerin işlevi ve “oyun” kavramının mitlerle ilişkisinden, ardından Levi-Strauss ve Roland Barthes’ın mit yaklaşımları ve analizinden bahsedilmiş, ardından “God of War III” adlı video oyununa mitsel çözümleme yapılmıştır. Her iki düşünürün mit yaklaşımları çerçevesinde ön...

76 FR 77561 - Atomic Safety and Licensing Board; In the Matter of Progress Energy Florida, Inc.; (Levy County...

Science.gov (United States)

2011-12-13

...] Atomic Safety and Licensing Board; In the Matter of Progress Energy Florida, Inc.; (Levy County Nuclear....\\1\\ On February 23, 2009, this Board was established to handle the matter and to preside over any... resulting from active and passive dewatering; 2. Impacts resulting from the connection of the site to the...

77 FR 51832 - Atomic Safety and Licensing Board; In the Matter of Progress Energy Florida, Inc. (Levy County...

Science.gov (United States)

2012-08-27

...] Atomic Safety and Licensing Board; In the Matter of Progress Energy Florida, Inc. (Levy County Nuclear... testimony are being heard, all of the proceedings will be open to the public. See 10 CFR 2.328. A. Matters.... Impacts resulting from active and passive dewatering; 2. Impacts resulting from the connection of the site...

Memory and testimony in Primo Levi: the Babel of the concentration camps

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María Coira

2014-08-01

Full Text Available Memory as a problem and the subject of theoretical inquiry, although early onset in civilization that we call western, has gained an important place in the concerns of historians, philosophers, psychologists, and literary critics, with all the ethical implications, political and aesthetic that entails. In this context, special dimensions such problematic charged when what is narrated, analyzes, represents or attempts to explain what are the collective traumatic events. In this paper, we focus on some aspects of testimonial texts and essays of Primo Levi (1919-1987, which estimates as unavoidable regarding the aforementioned issues. These texts are: Se questo è un uomo (1947, La tregua (1963 and I sommersi e i salvati (1986.

The quadratic-form identity for constructing Hamiltonian structures of the NLS-MKdV hierarchy and multi-component Levi hierarchy

International Nuclear Information System (INIS)

Dong Huanhe; Wang Xiangrong

2008-01-01

The trace identity is extended to the quadratic-form identity. The Hamiltonian structures of the NLS-MKdV hierarchy, and integrable coupling of multi-component Levi hierarchy are obtained by the quadratic-form identity. The method can be used to produce the Hamiltonian structures of the other integrable couplings or multi-component hierarchies

The witness indiscreet window: Primo Levi and surrealism after Auschwitz

Directory of Open Access Journals (Sweden)

Anna Basevi

2015-12-01

Full Text Available Primo Levi, renowned for his testimony of Nazi camp (If This Is a Man, 1947, published a collection of short stories entitled “Natural Tales”. He uses the surrealistic elements and plots to imagine the paradoxical consequences of human rationality. “Angelic Butterfly” relates to the theme of genetic experiments during Nazism and stands out for horror elements and drama. This tale’s re­lation to the post-Auschwitz reflection lies firstly in its structure which raises the question of the wit­ness; secondly, in the uncertain effect of the “imaginable” as it questions the fragile boundary be­tween real, possible and fantastic; thirdly in the narrative organization based on the connection of the ideas of trace, fragment and testimony. In my analysis I will expose how this text is marked by one of the most traumatic events of the twentieth century.

The Relationship between Components of the Ohio Local School District Report Card and the Outcome of a School Tax Levy

Science.gov (United States)

Wheatley, Vicki Ann

2012-01-01

The relationship between components of the local school district report card, school district typology, and the outcome of public school tax levy requests were examined in this study. A correlation research design was used to measure the relationship between the independent variables (performance index, average yearly progress, value added,…

'Big bang' of quantum universe

International Nuclear Information System (INIS)

Pawlowski, M.; Pervushin, V.N.

2000-01-01

The reparametrization-invariant generating functional for the unitary and causal perturbation theory in general relativity in a finite space-time is obtained. The classical cosmology of a Universe and the Faddeev-Popov-DeWitt functional correspond to different orders of decomposition of this functional over the inverse 'mass' of a Universe. It is shown that the invariant content of general relativity as a constrained system can be covered by two 'equivalent' unconstrained systems: the 'dynamic' (with 'dynamic' time as the cosmic scale factor and conformal field variables) and 'geometric' (given by the Levi-Civita type canonical transformation to the action-angle variables which determine initial cosmological states with the arrow of the proper time measured by the watch of an observer in the comoving frame). 'Big Bang', the Hubble evolution, and creation of 'dynamic' particles by the 'geometric' vacuum are determined by 'relations' between the dynamic and geometric systems as pure relativistic phenomena, like the Lorentz-type 'relation' between the rest and comoving frames in special relativity

Pengaruh Harga Diskon, Kualitas Produk, Citra Merek, dan Iklan terhadap Minat Beli Celana Jeans Levi's di Surabaya

OpenAIRE

Ghristian, Ignatius Danu

2015-01-01

The aim of this study is to test the effect of Discounted Price, Product Quality, Brand Image, and Advertising on Purchase Intention of Levi's Pants Jeans in Surabaya. This study used the independent variables such as discount price, product quality, brand image and advertising while the dependent variable is Purchase Intention. It took 82 respondents that were selected by using Judgment Sampling Technique. The data were analyzed using multiple linear regressions and using analysis tools of S...

Homage to Rita Levi-Montalcini, the queen of modern neuroscience.

Science.gov (United States)

Aloe, Luigi; Chaldakov, George N

2013-08-01

The first cell growth factor, nerve growth factor (NGF), was discovered by Rita Levi-Montalcini (RLM) in the early 1950s. Originally identified as neurite outgrowth-stimulating factor, later studies revealed that non-neuronal cells, including immune cells, endothelial cells, cardiomyocytes, pancreatic beta cells, prostate epithelial and adipose tissue cells, were also targets for and/or sources of NGF. Nerve growth factor is well recognised as mediating multiple biological phenomena, ranging from the neurotrophic through immunotrophic and epitheliotrophic to metabotrophic effects. Consequently, NGF and other members of the neurotrophin family are implicated in the pathogenesis of a large spectrum of neuronal and non-neuronal diseases, ranging from Alzheimer's and other neurodegenerative diseases to atherosclerosis and cardiometabolic disorders. Recent studies have demonstrated the therapeutic potentials of NGF in these conditions, including ocular and cutaneous diseases. NGF TrkA receptor antagonists emerged as novel drugs for pain, prostate and breast cancer, melanoma and urinary bladder syndromes. Here, we briefly describe the 'unpredictable' ideogenesis of the discovery of NGF, a eureka in the neuroscience. © 2013 International Federation for Cell Biology.

Bitcoinin omaksumisen ja leviämisen mahdollisuudet maksuvälineenä vähittäiskauppa-alalla : Case: Bitcoinkaupat

OpenAIRE

Virtanen, Joni

2015-01-01

Opinnäytetyön tarkoituksena oli selvittää bitcoinin omaksumisen ja leviämisen mahdollisuudet vähittäiskauppa-alalla. Opinnäytetyön toimeksiantajana oli Bitcoinkaupat, joka tarjoaa yrityksille bitcoin-maksujen vastaanottamisen mahdollistavaa BitPay-maksupalvelua. Tavoitteena oli tulosten perusteella muodostaa kokonaiskuva vähittäiskauppa-alan asenteista virtuaalivaluutta bitcoinia kohtaan BitPay-maksupalvelun myynnin ja markkinoinnin tehostamiseksi. Tavoitteena oli myös uusien asiakasyritysten...

Excitation energies from Görling-Levy perturbation theory along the range-separated adiabatic connection

Science.gov (United States)

Rebolini, Elisa; Teale, Andrew M.; Helgaker, Trygve; Savin, Andreas; Toulouse, Julien

2018-06-01

A Görling-Levy (GL)-based perturbation theory along the range-separated adiabatic connection is assessed for the calculation of electronic excitation energies. In comparison with the Rayleigh-Schrödinger (RS)-based perturbation theory this GL-based perturbation theory keeps the ground-state density constant at each order and thus gives the correct ionisation energy at each order. Excitation energies up to first order in the perturbation have been calculated numerically for the helium and beryllium atoms and the hydrogen molecule without introducing any density-functional approximations. In comparison with the RS-based perturbation theory, the present GL-based perturbation theory gives much more accurate excitation energies for Rydberg states but similar excitation energies for valence states.

Change in non-alcoholic beverage sales following a 10-pence levy on sugar-sweetened beverages within a national chain of restaurants in the UK: interrupted time series analysis of a natural experiment.

Science.gov (United States)

Cornelsen, Laura; Mytton, Oliver T; Adams, Jean; Gasparrini, Antonio; Iskander, Dalia; Knai, Cecile; Petticrew, Mark; Scott, Courtney; Smith, Richard; Thompson, Claire; White, Martin; Cummins, Steven

2017-11-01

This study evaluates changes in sales of non-alcoholic beverages in Jamie's Italian, a national chain of commercial restaurants in the UK, following the introduction of a £0.10 per-beverage levy on sugar-sweetened beverages (SSBs) and supporting activity including beverage menu redesign, new products and establishment of a children's health fund from levy proceeds. We used an interrupted time series design to quantify changes in sales of non-alcoholic beverages 12 weeks and 6 months after implementation of the levy, using itemised electronic point of sale data. Main outcomes were number of SSBs and other non-alcoholic beverages sold per customer. Linear regression and multilevel random effects models, adjusting for seasonality and clustering, were used to investigate changes in SSB sales across all restaurants (n=37) and by tertiles of baseline restaurant SSB sales per customer. Compared with the prelevy period, the number of SSBs sold per customer declined by 11.0% (-17.3% to -4.3%) at 12 weeks and 9.3% (-15.2% to -3.2%) at 6 months. For non-levied beverages, sales per customer of children's fruit juice declined by 34.7% (-55.3% to -4.3%) at 12 weeks and 9.9% (-16.8% to -2.4%) at 6 months. At 6 months, sales per customer of fruit juice increased by 21.8% (14.0% to 30.2%) but sales of diet cola (-7.3%; -11.7% to -2.8%) and bottled waters (-6.5%; -11.0% to -1.7%) declined. Changes in sales were only observed in restaurants in the medium and high tertiles of baseline SSB sales per customer. Introduction of a £0.10 levy on SSBs alongside complementary activities is associated with declines in SSB sales per customer in the short and medium term, particularly in restaurants with higher baseline sales of SSBs. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Showmaker-Levy 9 and plume-forming collisions on Earth

Energy Technology Data Exchange (ETDEWEB)

Boslough, M.B.E.; Crawford, D.A.

1995-12-31

Computational models for the July, 1994 collision of comet Shoemaker-Levy 9 with Jupiter have provided a framework for interpreting the observational data. Imaging, photometry, and spectroscopy data from ground-based, Hubble Space Telescope, and Galileo spacecraft instruments are consistent with phenomena that were dominated by the generation of incandescent fireballs that were ballistically ejected to high altitudes, where they formed plumes that subsequently collapsed over large areas of Jupiter`s atmosphere. Applications of similar computational models to collisions into Earth`s atmosphere show that a very similar sequence of events should take place for NEO impacts with energies as low as 3 megatons, recurring on 100 year timescales or less. This result suggests that the 1908 Tunguska event was a plume-forming atmospheric explosion, and that some of the phenomena associated with it might be related to the ejection and collapse of a high plume. Hazards associated with plume growth and collapse should be included in the evaluation of the impact threat to Earth, and opportunities should be sought for observational validation of atmospheric impact models by exploiting data already being collected from the natural flux of multi-kiloton to megaton sized objects that constantly enter Earth`s atmosphere on annual to decadal timescales.

[Doctor Levi B. Salmans, founder of The Good Samaritan sanitarium in Guanajuato].

Science.gov (United States)

Olivier-Toledo, Carlos; Viesca-Treviño, Carlos

2016-01-01

In this research we focus on the medical evangelist Levi B. Salmans, and The Good Samaritan sanitarium. Doctor Salmans lived in Mexico for about 50 years (1885-1935). During the first part of his stay, he was devoted to found churches and Methodist schools. However, from 1891 he took a turn in his career by founding dispensaries in different towns of Guanajuato to create, in 1899, the private charity association for the sick and infirm The Good Samaritan. His intense, intellectual, and practical work led him to create health journals, to train nurses, and to promote physiotherapies in accordance with the science advances of that time. By itself, this research shows that the history of medicine in Mexico still has long way to go and that Protestant communities, in favor of modernity and scientific knowledge, took a big part in shaping the history of this discipline in Mexico.

Is the Market Portfolio Efficient? A New Test to Revisit the Roll (1977) versus Levy and Roll (2010) Controversy

OpenAIRE

Marie Brière; Bastien Drut; Valérie Mignon; Kim Oosterlinck; Ariane Szafarz

2011-01-01

Levy and Roll (Review of Financial Studies, 2010) have recently revived the debate related to the market portfolio's efficiency suggesting that it may be mean-variance efficient after all. This paper develops an alternative test of portfolio mean-variance efficiency based on the realistic assumption that all assets are risky. The test is based on the vertical distance of a portfolio from the efficient frontier. Monte Carlo simulations show that our test outperforms the previous mean-variance ...

The Patch-Levy-Based Bees Algorithm Applied to Dynamic Optimization Problems

Directory of Open Access Journals (Sweden)

Wasim A. Hussein

2017-01-01

Full Text Available Many real-world optimization problems are actually of dynamic nature. These problems change over time in terms of the objective function, decision variables, constraints, and so forth. Therefore, it is very important to study the performance of a metaheuristic algorithm in dynamic environments to assess the robustness of the algorithm to deal with real-word problems. In addition, it is important to adapt the existing metaheuristic algorithms to perform well in dynamic environments. This paper investigates a recently proposed version of Bees Algorithm, which is called Patch-Levy-based Bees Algorithm (PLBA, on solving dynamic problems, and adapts it to deal with such problems. The performance of the PLBA is compared with other BA versions and other state-of-the-art algorithms on a set of dynamic multimodal benchmark problems of different degrees of difficulties. The results of the experiments show that PLBA achieves better results than the other BA variants. The obtained results also indicate that PLBA significantly outperforms some of the other state-of-the-art algorithms and is competitive with others.

Gadamer, O’Gorman, Levi. Combates contra el neopositivismo historiográfico y contra el fetiche del documento

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Morelos Torres Aguilar

2014-01-01

Full Text Available El artículo analiza críticamente, a partir de las consideraciones de Giovanni Levi, Hans-Georg Gadamer y Edmundo O’Gorman, la manera en que los historiadores aprehenden los acontecimientos y el procedimiento mediante el cual obtienen y utilizan sus fuentes. Las ideas de estos tres pensadores cuestionan, desde distintas perspectivas, la preeminencia de una heurística basada sólo en la afanosa búsqueda de la verdad, característica de la escuela científica alemana y el positivismo, corrientes ambas del siglo XIX; proponen en cambio, como alternativa que mucho debe a Ser y tiempo de Heidegger, la comprensión e interpretación de los procesos y los sujetos históricos, como una forma adecuada de explicación histórica. The article critically analyzes, from the considerations of Giovanni Levi, Hans-Georg Gadamer and Edmundo O’Gorman, the way in which the historians apprehend the events and the procedure by means of which they obtain and use his sources. The ideas of these three thinkers question, from different perspectives, the preeminence of a heuristic based only on the eager search of the truth, characteristic of the scientific german school and the positivism, currents both of the 19th century; they propose on the other hand, as alternative that much owes to Being and time of Heidegger, the comprehension and interpretation of the processes and the historical subjects, as a suitable form of historical explanation.

Edipo, Kant y P.Levi: una reflexión sobre la autonomía de la voluntad

OpenAIRE

Bermejo Barrera, José Carlos

2003-01-01

En este trabajo se lleva a cabo un análisis literario y filosófico de tipo comparativo, en el que se establece un paralelo entre la concepción griega de la autonomía limitada de la voluntad, la concepción ilustrada europea ¿encarnada por Kant- de la autonomía plena de la misma, y la expuesta por P. Levi en su reflexión sobre el totalitarismo. Se concluye que la visión griega posee más interés para comprender el mundo actual que la visión ilustrada.

Tight Error Bounds for Fourier Methods for Option Pricing for Exponential Levy Processes

KAUST Repository

Crocce, Fabian

2016-01-06

Prices of European options whose underlying asset is driven by the L´evy process are solutions to partial integrodifferential Equations (PIDEs) that generalise the Black-Scholes equation by incorporating a non-local integral term to account for the discontinuities in the asset price. The Levy -Khintchine formula provides an explicit representation of the characteristic function of a L´evy process (cf, [6]): One can derive an exact expression for the Fourier transform of the solution of the relevant PIDE. The rapid rate of convergence of the trapezoid quadrature and the speedup provide efficient methods for evaluationg option prices, possibly for a range of parameter configurations simultaneously. A couple of works have been devoted to the error analysis and parameter selection for these transform-based methods. In [5] several payoff functions are considered for a rather general set of models, whose characteristic function is assumed to be known. [4] presents the framework and theoretical approach for the error analysis, and establishes polynomial convergence rates for approximations of the option prices. [1] presents FT-related methods with curved integration contour. The classical flat FT-methods have been, on the other hand, extended for option pricing problems beyond the European framework [3]. We present a methodology for studying and bounding the error committed when using FT methods to compute option prices. We also provide a systematic way of choosing the parameters of the numerical method, minimising the error bound and guaranteeing adherence to a pre-described error tolerance. We focus on exponential L´evy processes that may be of either diffusive or pure jump in type. Our contribution is to derive a tight error bound for a Fourier transform method when pricing options under risk-neutral Levy dynamics. We present a simplified bound that separates the contributions of the payoff and of the process in an easily processed and extensible product form that

‘From “bad” to “good”: Baroque architecture through a century of art historiography and politics’: Evonne Levy, Baroque and the Political Language of Formalism (1845-1945: Burckhardt, Wölfflin, Gurlitt, Brinckmann, Sedlmayr, 400 pp., 42 ills, Basel: Schwabe, 2015

Directory of Open Access Journals (Sweden)

Marco M. Mascolo

2016-12-01

Full Text Available The political element in art history has often played a crucial role and has been individuated as such for artists or their clients. But the political elements that shaped art historical theories or pattern of interpretations are not always clearly addressed as object of analysis. With this book Evonne Levy offers an explanation of the role politics and historical circumstances had on the shaping of an art-historical discourse between 1845 and 1945, focusing her attention on five major Germanophone scholars that had a crucial role in the rediscovery and study of the architectural Baroque. The concept was, as Levy argues in this book, a perfect example to detect the political implications of formalism, which in its reception is often considered apolitical. Aiming to situate formalism in its historical context, Levy focuses primarily on characterising formalist researches about Baroque through the political and philosophical elements that influenced Jacob Burckhardt, Heinrich Wölfflin, Cornelius Gurlitt, Albert Erich Brinckmann and Hans Sedlmayr between the nineteenth and twentieth centuries. Levy demonstrates how Baroque, from a ‘bad’ style and a ‘bad’ element in German art hds gradually become a ‘good’ element of art-historical discourse, situating it at the crossroad between art history and politics.

Por um lugar no império: inglesidade, pertencimento negro e memória nacional em dois contos de Andrea Levy

Directory of Open Access Journals (Sweden)

Denise Almeida Silva

2017-01-01

Full Text Available http://dx.doi.org/10.5007/2175-8026.2017v70n1p17 Este trabalho objetiva examinar a interrogação da inglesidade (Englishness pela  ficcionista britânica negra Andrea Levy a partir do lugar ocupado por ela como cidadã britânica, descendente de migrantes caribenhos negros.  O questionamento é situado no quadro da construção identitária que segue ao contato dos ingleses com seus outros, especialmente no contexto da geração Windrush. Entrevistas e, sobretudo, o ensaio “Back to my own country” ajudam a dimensionar a influência da prática e pensamento racista tanto nas relações sociais e culturais quanto na invisibilização da escravidão negra na história oficial da Inglaterra. Considera-se a escrita como a forma escolhida por Levy para posicionar-se frente a essa omissão histórica, e  analisam-se, como forma de exemplificar tal práxis ficcional,  dois contos que visibilizam as relações entre os coloniais negros e a população hegemônica inglesa, “The polite way that English people have” e “The empty pram”.

Exact exchange and Wilson-Levy correlation: a pragmatic device for studying complex weakly-bonded systems.

Science.gov (United States)

Walsh, T R

2005-02-07

The Wilson-Levy (WL) correlation functional is used together with Hartree-Fock (HF) theory to evaluate interaction energies at intermediate separations (i.e. around equilibrium separation) for several weakly-bonded systems. The HF+WL approach reproduces binding trends for all complexes studied: selected rare-gas dimers, isomers of the methane dimer, benzene dimer and naphthalene dimer, and base-pair stacking structures for pyrimidine, cytosine, uracil and guanine dimers. These HF+WL data are contrasted against results obtained from some popular functionals (including B3LYP and PBE), as well as two newly-developed functionals, X3LYP and xPBE. The utility of HF+WL, with reference to exact-exchange (EXX) density-functional theory, is discussed in terms of a suggested EXXWL exchange-correlation functional.

Die Wahrnehmung der Figur „Adolf Hitler“ in Daniel Levys „Mein Führer- die wirklich wahrste Wahrheit über Adolf Hitler“ durch internationales Filmpublikum.

OpenAIRE

Herzner, Dominik

2017-01-01

Filme beeinflussen die Wahrnehmungen von Figuren. Daniel Levys Film "Mein Führer" (die erste deutschsprachige Komödie über Adolf Hitler) führte zu einer positiven Wahrnehmung der Hauptfigur. In einer empirischen Untersuchung wurde gezeigt, dass sich dieser Effekt bei internationalem Filmpublikum, die einen anderen Zugang zur Thematik Nationalsozialismus haben, verstärkt.

Interações, poder e instituições totais: a narrativa de Primo Levi e a microssociologia de Erving Goffman

Directory of Open Access Journals (Sweden)

Robson dos Santos

2009-10-01

Full Text Available A partir do relato biográfico e literário produzido pelo sobrevivente de um campo de concentração - o judeu italiano Primo Levi -, que descreve as estratégias de interação e representação adotadas pelo narrador-sobrevivente para garantir a manutenção da vida, o presente artigo ensaia algumas reflexões sobre a Sociologia de Erving Goffman. O texto busca apreender os processos de produção da subjetividade e da individualidade no interior de uma instituição total, compreendendo o papel dos espaços sociais na construção de interações particulares, tal como aquelas que aconteceram num campo de extermínio, a partir do relato presente no livro "É isto um homem?", de Primo Levi. Essa análise nos conduz à reflexão sobre o micro e o macro na Sociologia de Goffman, bem como à indagação sobre a existência de uma teoria das instituições em sua Sociologia. Assim, ao adentrarmos essa dimensão da obra de Goffman com o auxílio da descrição da experiência de Primo Levi em uma instituição total, buscamos tanto dispor de uma narrativa diversa sobre o espaço em questão, quanto extrair alguns questionamentos para a própria concepção de Goffman, principalmente no que se refere às formas pelas quais sua Sociologia permite dinamizar as interações particulares, a história e as estruturas sociais exteriores ao território interacional. Ao que nos parece, uma análise das interações imanentes a locais delimitados não entra em contradição com a percepção e a análise dos processos sociais amplos: o campo de extermínio, por exemplo, instituiu e produziu sociabilidades próprias, das quais o entendimento, porém, não exclui a necessidade de se compreender o processo de emergência do nazismo, a história dos grupos perseguidos, bem como o sentido do Holocausto em relação ao chamado "processo civilizatório" ou a uma forma particular de racionalidade moderna.

Fractional Fick's law: the direct way

International Nuclear Information System (INIS)

Neel, M C; Abdennadher, A; Joelson, M

2007-01-01

Levy flights, which are Markovian continuous time random walks possibly accounting for extreme events, serve frequently as small-scale models for the spreading of matter in heterogeneous media. Among them, Brownian motion is a particular case where Fick's law holds: for a cloud of walkers, the flux is proportional to the gradient of the probability density of finding a particle at some place. Levy flights resemble Brownian motion, except that jump lengths are distributed according to an α-stable Levy law, possibly showing heavy tails and skewness. For α between 1 and 2, a fractional form of Fick's law is known to hold in infinite media: that the flux is proportional to a combination of fractional derivatives or the order of α - 1 of the density of walkers was obtained as a consequence of a fractional dispersion equation. We present a direct and natural proof of this result, based upon a novel definition of usual fractional derivatives, involving a convolution and a limiting process. Taking account of the thus obtained fractional Fick's law yields fractional dispersion equation for smooth densities. The method adapts to domains, limited by boundaries possibly implying non-trivial modifications to this equation

Estimating the Operational Effect of a Bunker Levy: The Case of Handymax Bulk Carriers

DEFF Research Database (Denmark)

Kapetanis, George N.; Gkonis, Konstantinos G.; Psaraftis, Harilaos N.

penalty for the existing ships. In this paper the proposal for a Global Emissions fund will be presented and discussed as the most appropriate, easy to implement and flexible solution for an enforcement of a market based measure. At a second stage and using the emissions calculation and speed optimisation...... tool developed within the Laboratory for Maritime Transport of the National Technical University of Athens, simulations will be performed for a specified Bulk carrier and the corresponding to its fleet segment. A bunker levy will be implemented in the program and its effects will be studied in terms......Market based measures concerning air emissions from ships are very likely to be introduced in the next years, in an effort to cap Greenhouse Gas Emissions from ships. A lot of countries have presented their proposals to IMO and practically the majority of them are based on a form of a fuel price...

Detection of the 3.4 micron emission feature in Comets P/Brorsen-Metcalf and Okazaki-Levy-Rudenko (1989r) and an observational summary

International Nuclear Information System (INIS)

Brooke, T.Y.; Tokunaga, A.T.; Knacke, R.F.

1991-01-01

The 3.4 micron emission feature due to cometary organics was detected in Comets P/Brorsen-Metcalf and Okazaki-Levy-Rudenko (1989r). Features-to-continuum ratios in these two comets were higher than those expected from the trend seen in other comets to date. Three micron spectra of eight comets are reviewed. The 3.4 micron band flux is better correlated with the water production rate than with the dust production rate in this sample of comets. High feature-to-continuum ratios in P/Brorsen-Metcalf and Okazaki-Levy-Rudenko can be explained by the low dust-to-gas ratios of these two comets. The observations to date are consistent with cometary organics being present in all comets (even those for which no 3.4 micron feature was evident) at comparable abundances with respect to water. The emission mechanism and absolute abundance of the organics are not well determined; either gas-phase fluorescence or thermal emission from hot grains is consistent with the heliocentric distance dependence of the 3.4 micron band flux. There is an overall similarity in the spectral profiles of the 3.4 micron feature in comets; however, there are some potentially significant differences in the details of the spectra. 30 refs

The pectinases from Sphenophorus levis: Potential for biotechnological applications.

Science.gov (United States)

Habrylo, Olivier; Evangelista, Danilo Elton; Castilho, Priscila Vasques; Pelloux, Jérôme; Henrique-Silva, Flávio

2018-06-01

Pectinases represent about one fifth of the enzyme worldwide market due their wide range of biotechnological applications. Current commercial pectinases are exclusively obtained from microbial sources, but here we report a pectin methylesterase (Sl-PME) and an endo-polygalacturonase (Sl-EPG) bioprospected from the sugarcane weevil, Sphenophorus levis, which revealed good potential for industrial applications. Sl-PME and Sl-EPG were overexpressed in Pichia pastoris, purified and enzymatically characterized. Sl-EPG presents optimal activity at pH 4-5 and 50 °C, showing that it can be used for juice extraction and clarification. On the other hand, Sl-PME presents optimal activity at pH 6-8 and 40 °C, and thus, suitable for both acidic and alkaline processing, such as coffee and tea fermentation. Sl-EPG shows V max  = 3.23 mM/min, K M  = 2.4 g/L and k cat  = 418.6 s -1 . While Sl-PME shows V max  = 0.14 mM/min, K M  = 4.1 g/L and k cat  = 1.7 s -1 . A PG inhibitor (PGIP2) weakly interfered in the Sl-EPG activity and Sl-PME was not affected by a usual PME inhibitor. Moreover, these enzymes manifested synergistic action towards methylesterified pectin. Here, we propose these enzymes as novel alternative tools for the current commercial pectinases. Copyright © 2018 Elsevier B.V. All rights reserved.

In search of a place in the empire: englishness, black belonging and national memory in two short stories by Andrea Levy

OpenAIRE

Silva, Denise Almeida

2017-01-01

http://dx.doi.org/10.5007/2175-8026.2017v70n1p17This essay aims at investigating the interrogation of Englishness carried out by the black English writer Andrea Levy from within the place she occupies as an English citizen who descends from black Caribbean immigrants. This interrogation takes place in the context of the identity construction that follows the encounter between the English and their others, especially in the Windrush generation. Interviews and the essay “Back to my own country”...

Levy's distributions for statistical description of fractal structures; discontinuous metal films on dielectric substrates

International Nuclear Information System (INIS)

Dobierzewska-Mozrzymas, E.; Szymczak, G.; Bieganski, P.; Pieciul, E.

2003-01-01

The ranges of statistical description of the systems may be determined on the basis of the inverse power law of the Mandelbrot. The slope of the straight line representing the power law in a double-logarithmic plot, determined as -1/μ (μ being a critical exponent), characterizes the distribution of elements in the system. In this paper, the inverse power law is used to describe the statistical distribution of discontinuous metal films with higher coverage coefficients (near percolation threshold). For these films the critical exponent μ∼1, both the mean value and the variance are infinite. The objects with such microstructure are described according to the Levy distribution; Cauchy, inverse Gauss and inverse gamma distribution, respectively. The experimental histograms are compared with the calculated ones. Inhomogeneous metal films were obtained experimentally, their microstructures were examined by means of electron microscope. On the basis of electron micrographs, the fractal dimensions were determined for the metal films with coverage coefficient ranging from 0.35 to 1.00

The Multiple Life of Nerve Growth Factor: Tribute to Rita Levi-Montalcini (1909-2012

Directory of Open Access Journals (Sweden)

Luigi Aloe

2013-03-01

Full Text Available At the end of the 19th century, it was envisaged by Santiago Ramon y Cajal, but not, proven, that life at the neuronal level requires trophic support. The proof was obtained in the early 1950's by work initiated by Rita Levi-Montalcini (RLM discovering the nerve growth factor (NGF. Today, NGF and its relatives, collectively designated neurotrophins, are well recognized as mediators of multiple biological phenomena in health and disease, ranging from the neurotrophic through immunotrophic and epitheliotrophic to metabotrophic effects. Consequently, NGF and other neurotrophins are implicated in the pathogenesis of a large spectrum of neuronal and non-neuronal diseases, from Alzheimer's and other neurodegenerative diseases to atherosclerosis and other cardiometabolic diseases. Recent studies demonstrated the therapeutic potentials of NGF in these diseases, including ocular and cutaneous diseases. Furthermore, NGF TrkA receptor antagonists emerged as novel drugs for pain, prostate and breast cancer, melanoma, and urinary bladder syndromes. Altogether, NGF's multiple potential in health and disease is briefly described here.

The multiple life of nerve growth factor: tribute to rita levi-montalcini (1909-2012).

Science.gov (United States)

Aloe, Luigi; Chaldakov, George N

2013-03-01

At the end of the 19(th) century, it was envisaged by Santiago Ramon y Cajal, but not, proven, that life at the neuronal level requires trophic support. The proof was obtained in the early 1950's by work initiated by Rita Levi-Montalcini (RLM) discovering the nerve growth factor (NGF). Today, NGF and its relatives, collectively designated neurotrophins, are well recognized as mediators of multiple biological phenomena in health and disease, ranging from the neurotrophic through immunotrophic and epitheliotrophic to metabotrophic effects. Consequently, NGF and other neurotrophins are implicated in the pathogenesis of a large spectrum of neuronal and non-neuronal diseases, from Alzheimer's and other neurodegenerative diseases to atherosclerosis and other cardiometabolic diseases. Recent studies demonstrated the therapeutic potentials of NGF in these diseases, including ocular and cutaneous diseases. Furthermore, NGF TrkA receptor antagonists emerged as novel drugs for pain, prostate and breast cancer, melanoma, and urinary bladder syndromes. Altogether, NGF's multiple potential in health and disease is briefly described here.

Initial Flight Test of the Production Support Flight Control Computers at NASA Dryden Flight Research Center

Science.gov (United States)

Carter, John; Stephenson, Mark

1999-01-01

The NASA Dryden Flight Research Center has completed the initial flight test of a modified set of F/A-18 flight control computers that gives the aircraft a research control law capability. The production support flight control computers (PSFCC) provide an increased capability for flight research in the control law, handling qualities, and flight systems areas. The PSFCC feature a research flight control processor that is "piggybacked" onto the baseline F/A-18 flight control system. This research processor allows for pilot selection of research control law operation in flight. To validate flight operation, a replication of a standard F/A-18 control law was programmed into the research processor and flight-tested over a limited envelope. This paper provides a brief description of the system, summarizes the initial flight test of the PSFCC, and describes future experiments for the PSFCC.

Corporate strategies and clothing supply chains reshaping towards the United States: Levi Strauss & Co firm’s situation

Directory of Open Access Journals (Sweden)

Guadalupe García de León P.

2009-07-01

Full Text Available This article presents a summary of the corporate strategies of the Levi Strauss & Co. firm, a company that has had an important role in each one of the phases of Mexico’s process of integration into the global apparel production: the integration under the shared–production programs, the first stage of NAFTA, and the current stage of decline of Mexican exports and re–positioning of China. The central argument is that, by analyzing the competitive strategies of the leading firms of global apparel networks—as in the case of Levi’s—, we can get closer to the restructuring logic of these networks and understand the changing terms of the international insertion of the countries and firms involved, as in the case of Mexico.

Por um lugar no império: inglesidade, pertencimento negro e memória nacional em dois contos de Andrea Levy

OpenAIRE

Silva, Denise Almeida

2017-01-01

Resumo: Este trabalho objetiva examinar a interrogação da inglesidade (Englishness) pela ficcionista britânica negra Andrea Levy a partir do lugar ocupado por ela como cidadã britânica, descendente de imigrantes caribenhos negros. O questionamento é situado no quadro da construção identitária que segue ao contato dos ingleses com seus outros, especialmente no contexto da geração Windrush. Entrevistas e, sobretudo, o ensaio “Back to my own country” ajudam a dimensionar a influência da prática ...

The political economy of an energy tax: the United Kingdom's Climate Change Levy

Energy Technology Data Exchange (ETDEWEB)

Pearce, D. [University College, London (United Kingdom). Dept. of Economics

2006-03-15

Energy taxes designed to control energy consumption, and to assist the achievement of climate change control targets under the Kyoto Protocol, are fairly common in European Union countries. Yet many of these taxes bear little resemblance to the design guidance that is given in economics textbooks. Political economy analysis, in which the interaction of economics and political reality is emphasised, explains the gap between theoretical ideals and practical reality. A closer look at the factors that influence real world policy design should help policy-oriented economists in designing measures that have a greater chance of adoption. The end-result may well be nth-best solutions which simply have to be 'lived with'. But there may also be room for design improvements that still honour the political constraints of policy design. This paper illustrates these issues in the context of one tax, the UK Climate Change Levy. (author)

On the Drell-Levy-Yan relation to O(α2s)

International Nuclear Information System (INIS)

Bluemlein, J.; Ravindran, V.; Neerven, W.L. van; Rijksuniversiteit Leiden

2000-03-01

We study the validity of a relation by Drell, Levy and Yan (DLY) connecting the deep inelastic structure (DIS) functions and the single-particle fragmentation functions in e + e - annihilation which are defined in the spacelike (q 2 2 > 0) regions respectively. Here q denotes the momentum of the virtual photon exchanged in the deep inelastic scattering process or the annihilation process. An extension of the DLY-relation, which originally was only derived in the scaling parton model, to all orders in QCD leads to a connection between the two evolution kernels determining the q 2 -dependence of the DIS structure functions and the fragmentation functions respectively. In relation to this we derive the transformation relations between the space-and time-like splitting functions up to next-to-leading order (NLO) and the coefficient functions up to NNLO both for unpolarized and polarized scattering. It is shown that the evolution kernels describing the combined singlet evolution for the structure functions F 2 (x, Q 2 ), F L (x, Q 2 ) where Q 2 = vertical stroke q 2 vertical stroke or F 2 (x, Q 2 ), ∂F 2 (x,Q 2 )/∂ln(Q 2 ) and the corresponding fragmentation functions satisfy the DLY relation up to next-to-leading order. We also comment on a relation proposed by Gribov and Lipatov. (orig.)

Flight Test of an Intelligent Flight-Control System

Science.gov (United States)

Davidson, Ron; Bosworth, John T.; Jacobson, Steven R.; Thomson, Michael Pl; Jorgensen, Charles C.

2003-01-01

The F-15 Advanced Controls Technology for Integrated Vehicles (ACTIVE) airplane (see figure) was the test bed for a flight test of an intelligent flight control system (IFCS). This IFCS utilizes a neural network to determine critical stability and control derivatives for a control law, the real-time gains of which are computed by an algorithm that solves the Riccati equation. These derivatives are also used to identify the parameters of a dynamic model of the airplane. The model is used in a model-following portion of the control law, in order to provide specific vehicle handling characteristics. The flight test of the IFCS marks the initiation of the Intelligent Flight Control System Advanced Concept Program (IFCS ACP), which is a collaboration between NASA and Boeing Phantom Works. The goals of the IFCS ACP are to (1) develop the concept of a flight-control system that uses neural-network technology to identify aircraft characteristics to provide optimal aircraft performance, (2) develop a self-training neural network to update estimates of aircraft properties in flight, and (3) demonstrate the aforementioned concepts on the F-15 ACTIVE airplane in flight. The activities of the initial IFCS ACP were divided into three Phases, each devoted to the attainment of a different objective. The objective of Phase I was to develop a pre-trained neural network to store and recall the wind-tunnel-based stability and control derivatives of the vehicle. The objective of Phase II was to develop a neural network that can learn how to adjust the stability and control derivatives to account for failures or modeling deficiencies. The objective of Phase III was to develop a flight control system that uses the neural network outputs as a basis for controlling the aircraft. The flight test of the IFCS was performed in stages. In the first stage, the Phase I version of the pre-trained neural network was flown in a passive mode. The neural network software was running using flight data

Ultrarelativistic boost of a black hole in the magnetic universe of Levi-Civita-Bertotti-Robinson

Science.gov (United States)

Ortaggio, Marcello; Astorino, Marco

2018-05-01

We consider an exact Einstein-Maxwell solution constructed by Alekseev and Garcia, which describes a Schwarzschild black hole immersed in the magnetic universe of Levi-Civita, Bertotti, and Robinson (LCBR). After reviewing the basic properties of this spacetime, we study the ultrarelativistic limit in which the black hole is boosted to the speed of light, while sending its mass to 0. This results in a nonexpanding impulsive wave traveling in the LCBR universe. The wave front is a 2-sphere carrying two null point particles at its poles—a remnant of the structure of the original static spacetime. It is also shown that the obtained line element belongs to the Kundt class of spacetimes, and the relation with the known family of exact gravitational waves of finite duration propagating in the LCBR background is clarified. In the limit of a vanishing electromagnetic field, one point particle is pushed away to infinity and the single-particle Aichelburg-Sexl p p -wave propagating in Minkowski space is recovered.

In-Flight Sleep of Flight Crew During a 7-hour Rest Break: Implications for Research and Flight Safety

Science.gov (United States)

Signal, T. Leigh; Gander, Philippa H.; van den Berg, Margo J.; Graeber, R. Curtis

2013-01-01

Study Objectives: To assess the amount and quality of sleep that flight crew are able to obtain during flight, and identify factors that influence the sleep obtained. Design: Flight crew operating flights between Everett, WA, USA and Asia had their sleep recorded polysomnographically for 1 night in a layover hotel and during a 7-h in-flight rest opportunity on flights averaging 15.7 h. Setting: Layover hotel and in-flight crew rest facilities onboard the Boeing 777-200ER aircraft. Participants: Twenty-one male flight crew (11 Captains, mean age 48 yr and 10 First Officers, mean age 35 yr). Interventions: N/A. Measurements and Results: Sleep was recorded using actigraphy during the entire tour of duty, and polysomnographically in a layover hotel and during the flight. Mixed model analysis of covariance was used to determine the factors affecting in-flight sleep. In-flight sleep was less efficient (70% vs. 88%), with more nonrapid eye movement Stage 1/Stage 2 and more frequent awakenings per h (7.7/h vs. 4.6/h) than sleep in the layover hotel. In-flight sleep included very little slow wave sleep (median 0.5%). Less time was spent trying to sleep and less sleep was obtained when sleep opportunities occurred during the first half of the flight. Multivariate analyses suggest age is the most consistent factor affecting in-flight sleep duration and quality. Conclusions: This study confirms that even during long sleep opportunities, in-flight sleep is of poorer quality than sleep on the ground. With longer flight times, the quality and recuperative value of in-flight sleep is increasingly important for flight safety. Because the age limit for flight crew is being challenged, the consequences of age adversely affecting sleep quantity and quality need to be evaluated. Citation: Signal TL; Gander PH; van den Berg MJ; Graeber RC. In-flight sleep of flight crew during a 7-hour rest break: implications for research and flight safety. SLEEP 2013;36(1):109–115. PMID:23288977

Beyond Brownian Motion: A Levy Flight in Magic Boots -50 ...

Indian Academy of Sciences (India)

in the scientific community to observe molecular aggregates which travel at times .... tional Institutes of health analysed the time intervals between heart beats. ... mental and numerical methods to study a leaking tap. They found that the time ...

Por um lugar no império: inglesidade, pertencimento negro e memória nacional em dois contos de Andrea Levy

OpenAIRE

Denise Almeida Silva

2017-01-01

http://dx.doi.org/10.5007/2175-8026.2017v70n1p17 Este trabalho objetiva examinar a interrogação da inglesidade (Englishness) pela  ficcionista britânica negra Andrea Levy a partir do lugar ocupado por ela como cidadã britânica, descendente de migrantes caribenhos negros.  O questionamento é situado no quadro da construção identitária que segue ao contato dos ingleses com seus outros, especialmente no contexto da geração Windrush. Entrevistas e, sobretudo, o ensaio “Back to my own country”...

Proliferative thyroid lesions in three diplodactylid geckos: Nephrurus amyae, Nephrurus levis, and Oedura marmorata.

Science.gov (United States)

Hadfield, Catherine A; Clayton, Leigh A; Clancy, Meredith M; Beck, Sarah E; Mangus, Lisa M; Montali, Richard J

2012-03-01

Over a 5-mo period, three diplodactylid geckos housed at the National Aquarium were diagnosed with proliferative thyroid lesions: a rough knob-tail gecko (Nephrurus amyae), a smooth knob-tail gecko (Nephrurus levis), and a marbled velvet gecko (Oedura marmorata). Clinical signs included an intraoral mass or ventral throat swelling (or both), oral bleeding, and weight loss. Both of the knob-tail geckos died. The histologic diagnosis for the rough knob-tail gecko was thyroid carcinoma with metastases to the liver and lungs, and thyroid carcinoma with no metastases was reported in the smooth knob-tail gecko. A thyroidectomy was performed on the marbled velvet gecko with a histologic diagnosis of adenomatous hyperplasia. Postoperative weight loss and bradycardia resolved following oral supplementation with levothyroxine. The animal is in normal health 10 mo post-surgery. Five other diplodactylid geckos in the collection remain unaffected, giving a 38% prevalence of proliferative thyroid lesions (3/8). The etiology remains undetermined. This is the first report of a cluster of proliferative thyroid lesions in geckos.

O paraíso não é aqui: a violência contra a mulher emTatiana Salem Levy

Directory of Open Access Journals (Sweden)

Paula Queiroz Dutra

2016-01-01

Full Text Available Este trabajo tiene como objetivo analizar las representaciones de las distintas formas de violencia contra la mujer en la novela Paraíso (2014, de la escritora brasileña Tatiana Salem Levy. Se busca comprender y problematizar la representación del dolor del otro y del posicionamiento de las mujeres frente a situaciones de violencia dentro de la novela. Además, se pretende observar si la representación de la violencia sufrida por los personajes femeninos, tanto en el espacio público como en el doméstico, contribuye a una crítica a la violencia contra la mujer, deconstruyendo estereotipos de sumisión y victimización.

In-flight sleep of flight crew during a 7-hour rest break: implications for research and flight safety.

Science.gov (United States)

Signal, T Leigh; Gander, Philippa H; van den Berg, Margo J; Graeber, R Curtis

2013-01-01

To assess the amount and quality of sleep that flight crew are able to obtain during flight, and identify factors that influence the sleep obtained. Flight crew operating flights between Everett, WA, USA and Asia had their sleep recorded polysomnographically for 1 night in a layover hotel and during a 7-h in-flight rest opportunity on flights averaging 15.7 h. Layover hotel and in-flight crew rest facilities onboard the Boeing 777-200ER aircraft. Twenty-one male flight crew (11 Captains, mean age 48 yr and 10 First Officers, mean age 35 yr). N/A. Sleep was recorded using actigraphy during the entire tour of duty, and polysomnographically in a layover hotel and during the flight. Mixed model analysis of covariance was used to determine the factors affecting in-flight sleep. In-flight sleep was less efficient (70% vs. 88%), with more nonrapid eye movement Stage 1/Stage 2 and more frequent awakenings per h (7.7/h vs. 4.6/h) than sleep in the layover hotel. In-flight sleep included very little slow wave sleep (median 0.5%). Less time was spent trying to sleep and less sleep was obtained when sleep opportunities occurred during the first half of the flight. Multivariate analyses suggest age is the most consistent factor affecting in-flight sleep duration and quality. This study confirms that even during long sleep opportunities, in-flight sleep is of poorer quality than sleep on the ground. With longer flight times, the quality and recuperative value of in-flight sleep is increasingly important for flight safety. Because the age limit for flight crew is being challenged, the consequences of age adversely affecting sleep quantity and quality need to be evaluated.

to view fulltext PDF

Indian Academy of Sciences (India)

12 Routers in Internetworks. N Pon Saravanan. How Data Travels Through the Internet. Prashant Bharadwaj. 26 Biodiversity and Biological Degradation of Soil. Upasana Mishra and Dolly Wattal Dhar. 34 Nuclear Magnetic Resonance Spectroscopy. Susanta Das. 50 Beyond Brownian Motion: A Levy Flight in. Magic Boots.

Education Funding Crisis in the Suburbs: The Impact of the 2007-09 Recession Recovery Policies and the New York State Tax Levy Cap on School District Financial Planning Practices

Science.gov (United States)

Galligan, John J.; Annunziato, Anthony

2017-01-01

This article examines the impact of the fiscal recovery policies stemming from the 2007-09 economic recession and the implementation of the 2011 New York State Property Tax Levy Cap on the budgets of school districts located within a Long Island, New York suburban township. The research basis of this paper is based on two studies conducted by the…

Miracle Flights

Science.gov (United States)

... a Flight Get Involved Events Shop Miles Contact Miracle Flights Blog Giving Tuesday 800-359-1711 Thousands of children have been saved, but we still have miles to go. Request a Flight Click Here to Donate - Your ...

Anomalous particle diffusion and Levy random walk of magnetic field lines in three dimensional solar wind turbulence

International Nuclear Information System (INIS)

Zimbardo, G.

2005-01-01

Plasma transport in the presence of turbulence depends on a variety of parameters like the fluctuation level ? B/B0, the ratio between the particle Larmor radius and the turbulence correlation lengths, and the turbulence anisotropy. In this presentation, we review the results of numerical simulations of plasma and magnetic field line transport in the case of anisotropic magnetic turbulence, for parameter values close to those of the solar wind. We assume a uniform background magnetic field B0 = B0ez and a Fourier representation for magnetic fluctuations, with wavectors forming any angle with respect to B0. The energy density spectrum is a power law, and in k space the constant amplitude surfaces are ellipsoids, described by the correlation lengths lx, ly, lz, which quantify the anisotropy of turbulence. For magnetic field lines, we find that transport perpendicular to the background field depends on the Kubo number R = ? B B0 lz lx . For small Kubo numbers, R ? 1, we find anomalous, non Gaussian transport regimes (both sub and superdiffusive) which can be described as a Levy random walk. Increasing the Kubo number, i.e., the fluctuation level ? B/B0 and/or the ratio lz/lx, we find first a quasilinear and then a percolative regime, both corresponding to Gaussian diffusion. For particles, we find that transport parallel and perpendicular to the background magnetic field heavily depends on the turbulence anisotropy and on the particle Larmor radius. For turbulence levels typical of the solar wind, ? B/B0 ? 0.5 ?1, when the ratio between the particle Larmor radius and the turbulence correlation lengths is small, anomalous regimes are found in the case lz/lx ? 1, with Levy random walk (superdiffusion) along the magnetic field and subdiffusion in the perpendicular directions. Conversely, for lz/lx > 1 normal, Gaussian diffusion is found. Increasing the ratio between the particle Larmor radius and the turbulence correlation lengths, the parallel superdiffusion is

A significação do grotesco na narrativa de testemunho de Primo Levi

Directory of Open Access Journals (Sweden)

Viviane Dantas Moraes

2013-11-01

Full Text Available O grotesco, para Wolfgang Kayser, é um conceito que possui como essência estética a deformidade. Esta deformidade, normalmente, se revela por meio da escritura do corpo e imagens que causam abjeção. Primo Levi, ao relatar sua experiência enquanto prisioneiro nos campos de concentração rememora em sua narrativa algumas cenas que se aproximam fortemente do grotesco enquanto imagem e significação. Na sua maioria, se tratam de cenas fortes que, normalmente, se referem às pestes que assolavam o lugar, como os piolhos, assim como as doenças que debilitavam o corpo e as feridas crônicas nos pés. Em uma situação como esta, em que relembrar é doloroso, pois envolve a questão traumática, a tentativa de avaliar a própria dor muitas vezes se torna insuportável, por isso, é possível observar nestas descrições grotescas, aliás, algo frequente no campo de concentração, uma tentativa de externar e revelar um estado de alma em agonia.

Flight Test Implementation of a Second Generation Intelligent Flight Control System

Science.gov (United States)

Williams-Hayes, Peggy S.

2005-01-01

The NASA F-15 Intelligent Flight Control System project team has developed a series of flight control concepts designed to demonstrate the benefits of a neural network-based adaptive controller. The objective of the team was to develop and flight-test control systems that use neural network technology, to optimize the performance of the aircraft under nominal conditions, and to stabilize the aircraft under failure conditions. Failure conditions include locked or failed control surfaces as well as unforeseen damage that might occur to the aircraft in flight. The Intelligent Flight Control System team is currently in the process of implementing a second generation control scheme, collectively known as Generation 2 or Gen 2, for flight testing on the NASA F-15 aircraft. This report describes the Gen 2 system as implemented by the team for flight test evaluation. Simulation results are shown which describe the experiment to be performed in flight and highlight the ways in which the Gen 2 system meets the defined objectives.

A janela indiscreta da testemunha: Primo Levi e o fantástico pós-Auschwitz

Directory of Open Access Journals (Sweden)

Anna Basevi

2015-06-01

Full Text Available Primo Levi, mundialmente conhecido por seu testemunho do campo de extermínio (Se questo è un uomo, 1947 publicou uma coletânea de contos intitulados Histórias naturais onde utiliza os recursos do fantástico para imaginar as consequências paradoxais da racionalidade humana. A narrativa “Borboleta angélica” destaca-se pelos elementos do horror e do drama, relacionados ao tema das experiências genéticas durante o nazismo. O interesse deste conto e a sua especificidade pós-Auschwitz reside em alguns aspectos: em primeiro lugar em sua estrutura que reflete a problemática sobre o testemunho; no efeito de incerteza que se produz entorno ao que seria “imaginável” questionando a frágil fronteira entre real, possível e fantástico; a organização narrativa a partir do eixo rastro-fragmento-testemunho. Veremos, desta forma, como o texto é marcado por um dos eventos mais traumáticos do século XX.

A Survey of Open-Source UAV Flight Controllers and Flight Simulators

DEFF Research Database (Denmark)

Ebeid, Emad Samuel Malki; Skriver, Martin; Terkildsen, Kristian Husum

2018-01-01

, which are all tightly linked to the UAV flight controller hardware and software. The lack of standardization of flight controller architectures and the use of proprietary closed-source flight controllers on many UAV platforms, however, complicates this work: solutions developed for one flight controller...... may be difficult to port to another without substantial extra development and testing. Using open-source flight controllers mitigates some of these challenges and enables other researchers to validate and build upon existing research. This paper presents a survey of the publicly available open...

The role of situation assessment and flight experience in pilots' decisions to continue visual flight rules flight into adverse weather.

Science.gov (United States)

Wiegmann, Douglas A; Goh, Juliana; O'Hare, David

2002-01-01

Visual flight rules (VFR) flight into instrument meteorological conditions (IMC) is a major safety hazard in general aviation. In this study we examined pilots' decisions to continue or divert from a VFR flight into IMC during a dynamic simulation of a cross-country flight. Pilots encountered IMC either early or later into the flight, and the amount of time and distance pilots flew into the adverse weather prior to diverting was recorded. Results revealed that pilots who encountered the deteriorating weather earlier in the flight flew longer into the weather prior to diverting and had more optimistic estimates of weather conditions than did pilots who encountered the deteriorating weather later in the flight. Both the time and distance traveled into the weather prior to diverting were negatively correlated with pilots' previous flight experience. These findings suggest that VFR flight into IMC may be attributable, at least in part, to poor situation assessment and experience rather than to motivational judgment that induces risk-taking behavior as more time and effort are invested in a flight. Actual or potential applications of this research include the design of interventions that focus on improving weather evaluation skills in addition to addressing risk-taking attitudes.

Theseus in Flight

Science.gov (United States)

1996-01-01

The twin pusher propeller-driven engines of the Theseus research aircraft can be clearly seen in this photo, taken during a 1996 research flight at NASA's Dryden Flight Research Center, Edwards, California. The Theseus aircraft, built and operated by Aurora Flight Sciences Corporation, Manassas, Virginia, was a unique aircraft flown at NASA's Dryden Flight Research Center, Edwards, California, under a cooperative agreement between NASA and Aurora. Dryden hosted the Theseus program, providing hangar space and range safety for flight testing. Aurora Flight Sciences was responsible for the actual flight testing, vehicle flight safety, and operation of the aircraft. The Theseus remotely piloted aircraft flew its maiden flight on May 24, 1996, at Dryden. During its sixth flight on November 12, 1996, Theseus experienced an in-flight structural failure that resulted in the loss of the aircraft. As of the beginning of the year 2000, Aurora had not rebuilt the aircraft. Theseus was built for NASA under an innovative, $4.9 million fixed-price contract by Aurora Flight Sciences Corporation and its partners, West Virginia University, Morgantown, West Virginia, and Fairmont State College, Fairmont, West Virginia. The twin-engine, unpiloted vehicle had a 140-foot wingspan, and was constructed largely of composite materials. Powered by two 80-horsepower, turbocharged piston engines that drove twin 9-foot-diameter propellers, Theseus was designed to fly autonomously at high altitudes, with takeoff and landing under the active control of a ground-based pilot in a ground control station 'cockpit.' With the potential ability to carry 700 pounds of science instruments to altitudes above 60,000 feet for durations of greater than 24 hours, Theseus was intended to support research in areas such as stratospheric ozone depletion and the atmospheric effects of future high-speed civil transport aircraft engines. Instruments carried aboard Theseus also would be able to validate satellite

A Simple Flight Mill for the Study of Tethered Flight in Insects.

Science.gov (United States)

Attisano, Alfredo; Murphy, James T; Vickers, Andrew; Moore, Patricia J

2015-12-10

Flight in insects can be long-range migratory flights, intermediate-range dispersal flights, or short-range host-seeking flights. Previous studies have shown that flight mills are valuable tools for the experimental study of insect flight behavior, allowing researchers to examine how factors such as age, host plants, or population source can influence an insects' propensity to disperse. Flight mills allow researchers to measure components of flight such as speed and distance flown. Lack of detailed information about how to build such a device can make their construction appear to be prohibitively complex. We present a simple and relatively inexpensive flight mill for the study of tethered flight in insects. Experimental insects can be tethered with non-toxic adhesives and revolve around an axis by means of a very low friction magnetic bearing. The mill is designed for the study of flight in controlled conditions as it can be used inside an incubator or environmental chamber. The strongest points are the very simple electronic circuitry, the design that allows sixteen insects to fly simultaneously allowing the collection and analysis of a large number of samples in a short time and the potential to use the device in a very limited workspace. This design is extremely flexible, and we have adjusted the mill to accommodate different species of insects of various sizes.

Bat flight: aerodynamics, kinematics and flight morphology.

Science.gov (United States)

Hedenström, Anders; Johansson, L Christoffer

2015-03-01

Bats evolved the ability of powered flight more than 50 million years ago. The modern bat is an efficient flyer and recent research on bat flight has revealed many intriguing facts. By using particle image velocimetry to visualize wake vortices, both the magnitude and time-history of aerodynamic forces can be estimated. At most speeds the downstroke generates both lift and thrust, whereas the function of the upstroke changes with forward flight speed. At hovering and slow speed bats use a leading edge vortex to enhance the lift beyond that allowed by steady aerodynamics and an inverted wing during the upstroke to further aid weight support. The bat wing and its skeleton exhibit many features and control mechanisms that are presumed to improve flight performance. Whereas bats appear aerodynamically less efficient than birds when it comes to cruising flight, they have the edge over birds when it comes to manoeuvring. There is a direct relationship between kinematics and the aerodynamic performance, but there is still a lack of knowledge about how (and if) the bat controls the movements and shape (planform and camber) of the wing. Considering the relatively few bat species whose aerodynamic tracks have been characterized, there is scope for new discoveries and a need to study species representing more extreme positions in the bat morphospace. © 2015. Published by The Company of Biologists Ltd.

Selected Flight Test Results for Online Learning Neural Network-Based Flight Control System

Science.gov (United States)

Williams-Hayes, Peggy S.

2004-01-01

The NASA F-15 Intelligent Flight Control System project team developed a series of flight control concepts designed to demonstrate neural network-based adaptive controller benefits, with the objective to develop and flight-test control systems using neural network technology to optimize aircraft performance under nominal conditions and stabilize the aircraft under failure conditions. This report presents flight-test results for an adaptive controller using stability and control derivative values from an online learning neural network. A dynamic cell structure neural network is used in conjunction with a real-time parameter identification algorithm to estimate aerodynamic stability and control derivative increments to baseline aerodynamic derivatives in flight. This open-loop flight test set was performed in preparation for a future phase in which the learning neural network and parameter identification algorithm output would provide the flight controller with aerodynamic stability and control derivative updates in near real time. Two flight maneuvers are analyzed - pitch frequency sweep and automated flight-test maneuver designed to optimally excite the parameter identification algorithm in all axes. Frequency responses generated from flight data are compared to those obtained from nonlinear simulation runs. Flight data examination shows that addition of flight-identified aerodynamic derivative increments into the simulation improved aircraft pitch handling qualities.

An Improved Marriage in Honey Bees Optimization Algorithm for Single Objective Unconstrained Optimization

Directory of Open Access Journals (Sweden)

Yuksel Celik

2013-01-01

Full Text Available Marriage in honey bees optimization (MBO is a metaheuristic optimization algorithm developed by inspiration of the mating and fertilization process of honey bees and is a kind of swarm intelligence optimizations. In this study we propose improved marriage in honey bees optimization (IMBO by adding Levy flight algorithm for queen mating flight and neighboring for worker drone improving. The IMBO algorithm’s performance and its success are tested on the well-known six unconstrained test functions and compared with other metaheuristic optimization algorithms.

14 CFR 121.412 - Qualifications: Flight instructors (airplane) and flight instructors (simulator).

Science.gov (United States)

2010-01-01

... (airplane) and flight instructors (simulator). 121.412 Section 121.412 Aeronautics and Space FEDERAL... OPERATIONS Training Program § 121.412 Qualifications: Flight instructors (airplane) and flight instructors (simulator). (a) For the purposes of this section and § 121.414: (1) A flight instructor (airplane) is a...

Performance improvement of optical CDMA networks with stochastic artificial bee colony optimization technique

Science.gov (United States)

Panda, Satyasen

2018-05-01

This paper proposes a modified artificial bee colony optimization (ABC) algorithm based on levy flight swarm intelligence referred as artificial bee colony levy flight stochastic walk (ABC-LFSW) optimization for optical code division multiple access (OCDMA) network. The ABC-LFSW algorithm is used to solve asset assignment problem based on signal to noise ratio (SNR) optimization in OCDM networks with quality of service constraints. The proposed optimization using ABC-LFSW algorithm provides methods for minimizing various noises and interferences, regulating the transmitted power and optimizing the network design for improving the power efficiency of the optical code path (OCP) from source node to destination node. In this regard, an optical system model is proposed for improving the network performance with optimized input parameters. The detailed discussion and simulation results based on transmitted power allocation and power efficiency of OCPs are included. The experimental results prove the superiority of the proposed network in terms of power efficiency and spectral efficiency in comparison to networks without any power allocation approach.

Overview of Pre-Flight Physical Training, In-Flight Exercise Countermeasures and the Post-Flight Reconditioning Program for International Space Station Astronauts

Science.gov (United States)

Kerstman, Eric

2011-01-01

International Space Station (ISS) astronauts receive supervised physical training pre-flight, utilize exercise countermeasures in-flight, and participate in a structured reconditioning program post-flight. Despite recent advances in exercise hardware and prescribed exercise countermeasures, ISS crewmembers are still found to have variable levels of deconditioning post-flight. This presentation provides an overview of the astronaut medical certification requirements, pre-flight physical training, in-flight exercise countermeasures, and the post-flight reconditioning program. Astronauts must meet medical certification requirements on selection, annually, and prior to ISS missions. In addition, extensive physical fitness testing and standardized medical assessments are performed on long duration crewmembers pre-flight. Limited physical fitness assessments and medical examinations are performed in-flight to develop exercise countermeasure prescriptions, ensure that the crewmembers are physically capable of performing mission tasks, and monitor astronaut health. Upon mission completion, long duration astronauts must re-adapt to the 1 G environment, and be certified as fit to return to space flight training and active duty. A structured, supervised postflight reconditioning program has been developed to prevent injuries, facilitate re-adaptation to the 1 G environment, and subsequently return astronauts to training and space flight. The NASA reconditioning program is implemented by the Astronaut Strength, Conditioning, and Rehabilitation (ASCR) team and supervised by NASA flight surgeons. This program has evolved over the past 10 years of the International Space Station (ISS) program and has been successful in ensuring that long duration astronauts safely re-adapt to the 1 g environment and return to active duty. Lessons learned from this approach to managing deconditioning can be applied to terrestrial medicine and future exploration space flight missions.

Alternatives to the EEG levy. Possible effects of a reform of the energy transition financing on the industry; Alternativen zur EEG-Umlage. Moegliche Auswirkungen einer Reform der Energiewende-Finanzierung auf die Industrie

Energy Technology Data Exchange (ETDEWEB)

Scheyhing, Joerg [ECG Energie Consulting GmbH, Kehl (Germany)

2017-07-15

Although it has been adjusted six times since the year 2000, it has not yet been possible to manage the unrestricted growth of the EEG levy. In the 2017 election year, it becomes therefore ever more obvious that an alternative way to finance the energy transition is high on the political agenda. This would lead to significant changes for energy-intensive companies, regardless of whether they have benefited from a release from the levy or not. At the same time, the alternatives currently discussed have quite different effects on the industrial companies concerned and thereby the industry location Germany. [German] Obwohl seit dem Jahr 2000 inzwischen sechsmal angepasst, ist es bisher nicht gelungen, den ungebremsten Anstieg der EEG-Umlage in den Griff zu bekommen. Im Wahljahr 2017 wird deshalb immer offensichtlicher, dass ein alternativer Weg zur Finanzierung der Energiewende weit oben auf der politischen Tagesordnung steht. Damit kaemen auf die energieintensiven Unternehmen signifikante Veraenderungen zu, und zwar unabhaengig davon, ob sie bisher von einer Befreiung von der Umlage profitiert haben oder nicht. Dabei haben die derzeit diskutierten Alternativen durchaus unterschiedliche Auswirkungen auf die betroffenen Industrieunternehmen und damit den Wirtschaftsstandort Deutschland.

Advanced aircraft service life monitoring method via flight-by-flight load spectra

Science.gov (United States)

Lee, Hongchul

This research is an effort to understand current method and to propose an advanced method for Damage Tolerance Analysis (DTA) for the purpose of monitoring the aircraft service life. As one of tasks in the DTA, the current indirect Individual Aircraft Tracking (IAT) method for the F-16C/D Block 32 does not properly represent changes in flight usage severity affecting structural fatigue life. Therefore, an advanced aircraft service life monitoring method based on flight-by-flight load spectra is proposed and recommended for IAT program to track consumed fatigue life as an alternative to the current method which is based on the crack severity index (CSI) value. Damage Tolerance is one of aircraft design philosophies to ensure that aging aircrafts satisfy structural reliability in terms of fatigue failures throughout their service periods. IAT program, one of the most important tasks of DTA, is able to track potential structural crack growth at critical areas in the major airframe structural components of individual aircraft. The F-16C/D aircraft is equipped with a flight data recorder to monitor flight usage and provide the data to support structural load analysis. However, limited memory of flight data recorder allows user to monitor individual aircraft fatigue usage in terms of only the vertical inertia (NzW) data for calculating Crack Severity Index (CSI) value which defines the relative maneuver severity. Current IAT method for the F-16C/D Block 32 based on CSI value calculated from NzW is shown to be not accurate enough to monitor individual aircraft fatigue usage due to several problems. The proposed advanced aircraft service life monitoring method based on flight-by-flight load spectra is recommended as an improved method for the F-16C/D Block 32 aircraft. Flight-by-flight load spectra was generated from downloaded Crash Survival Flight Data Recorder (CSFDR) data by calculating loads for each time hack in selected flight data utilizing loads equations. From

Advanced Transport Operating System (ATOPS) Flight Management/Flight Controls (FM/FC) software description

Science.gov (United States)

Wolverton, David A.; Dickson, Richard W.; Clinedinst, Winston C.; Slominski, Christopher J.

1993-01-01

The flight software developed for the Flight Management/Flight Controls (FM/FC) MicroVAX computer used on the Transport Systems Research Vehicle for Advanced Transport Operating Systems (ATOPS) research is described. The FM/FC software computes navigation position estimates, guidance commands, and those commands issued to the control surfaces to direct the aircraft in flight. Various modes of flight are provided for, ranging from computer assisted manual modes to fully automatic modes including automatic landing. A high-level system overview as well as a description of each software module comprising the system is provided. Digital systems diagrams are included for each major flight control component and selected flight management functions.

Flight Planning

Science.gov (United States)

1991-01-01

Seagull Technology, Inc., Sunnyvale, CA, produced a computer program under a Langley Research Center Small Business Innovation Research (SBIR) grant called STAFPLAN (Seagull Technology Advanced Flight Plan) that plans optimal trajectory routes for small to medium sized airlines to minimize direct operating costs while complying with various airline operating constraints. STAFPLAN incorporates four input databases, weather, route data, aircraft performance, and flight-specific information (times, payload, crew, fuel cost) to provide the correct amount of fuel optimal cruise altitude, climb and descent points, optimal cruise speed, and flight path.

Comet Shoemaker-Levy 9/Jupiter collision observed with a high resolution speckle imaging system

Energy Technology Data Exchange (ETDEWEB)

Gravel, D. [Lawrence Livermore National Lab., CA (United States)

1994-11-15

During the week of July 16, 1994, comet Shoemaker-Levy 9, broken into 20 plus pieces by tidal forces on its last orbit, smashed into the planet Jupiter, releasing the explosive energy of 500 thousand megatons. A team of observers from LLNL used the LLNL Speckle Imaging Camera mounted on the University of California`s Lick Observatory 3 Meter Telescope to capture continuous sequences of planet images during the comet encounter. Post processing with the bispectral phase reconstruction algorithm improves the resolution by removing much of the blurring due to atmospheric turbulence. High resolution images of the planet surface showing the aftermath of the impact are probably the best that were obtained from any ground-based telescope. We have been looking at the regions of the fragment impacts to try to discern any dynamic behavior of the spots left on Jupiter`s cloud tops. Such information can lead to conclusions about the nature of the comet and of Jupiter`s atmosphere. So far, the Hubble Space Telescope has observed expanding waves from the G impact whose mechanism is enigmatic since they appear to be too slow to be sound waves and too fast to be gravity waves, given the present knowledge of Jupiter`s atmosphere. Some of our data on the G and L impact region complements the Hubble observations but, so far, is inconclusive about spot dynamics.

Flight Planning in the Cloud

Science.gov (United States)

Flores, Sarah L.; Chapman, Bruce D.; Tung, Waye W.; Zheng, Yang

2011-01-01

This new interface will enable Principal Investigators (PIs), as well as UAVSAR (Uninhabited Aerial Vehicle Synthetic Aperture Radar) members to do their own flight planning and time estimation without having to request flight lines through the science coordinator. It uses an all-in-one Google Maps interface, a JPL hosted database, and PI flight requirements to design an airborne flight plan. The application will enable users to see their own flight plan being constructed interactively through a map interface, and then the flight planning software will generate all the files necessary for the flight. Afterward, the UAVSAR team can then complete the flight request, including calendaring and supplying requisite flight request files in the expected format for processing by NASA s airborne science program. Some of the main features of the interface include drawing flight lines on the map, nudging them, adding them to the current flight plan, and reordering them. The user can also search and select takeoff, landing, and intermediate airports. As the flight plan is constructed, all of its components are constantly being saved to the database, and the estimated flight times are updated. Another feature is the ability to import flight lines from previously saved flight plans. One of the main motivations was to make this Web application as simple and intuitive as possible, while also being dynamic and robust. This Web application can easily be extended to support other airborne instruments.

Levy-Lieb-Based Monte Carlo Study of the Dimensionality Behaviour of the Electronic Kinetic Functional

Directory of Open Access Journals (Sweden)

Seshaditya A.

2017-06-01

Full Text Available We consider a gas of interacting electrons in the limit of nearly uniform density and treat the one dimensional (1D, two dimensional (2D and three dimensional (3D cases. We focus on the determination of the correlation part of the kinetic functional by employing a Monte Carlo sampling technique of electrons in space based on an analytic derivation via the Levy-Lieb constrained search principle. Of particular interest is the question of the behaviour of the functional as one passes from 1D to 3D; according to the basic principles of Density Functional Theory (DFT the form of the universal functional should be independent of the dimensionality. However, in practice the straightforward use of current approximate functionals in different dimensions is problematic. Here, we show that going from the 3D to the 2D case the functional form is consistent (concave function but in 1D becomes convex; such a drastic difference is peculiar of 1D electron systems as it is for other quantities. Given the interesting behaviour of the functional, this study represents a basic first-principle approach to the problem and suggests further investigations using highly accurate (though expensive many-electron computational techniques, such as Quantum Monte Carlo.

Advanced transport operating system software upgrade: Flight management/flight controls software description

Science.gov (United States)

Clinedinst, Winston C.; Debure, Kelly R.; Dickson, Richard W.; Heaphy, William J.; Parks, Mark A.; Slominski, Christopher J.; Wolverton, David A.

1988-01-01

The Flight Management/Flight Controls (FM/FC) software for the Norden 2 (PDP-11/70M) computer installed on the NASA 737 aircraft is described. The software computes the navigation position estimates, guidance commands, those commands to be issued to the control surfaces to direct the aircraft in flight based on the modes selected on the Advanced Guidance Control System (AGSC) mode panel, and the flight path selected via the Navigation Control/Display Unit (NCDU).

Free Flight Ground Testing of ADEPT in Advance of the Sounding Rocket One Flight Experiment

Science.gov (United States)

Smith, B. P.; Dutta, S.

2017-01-01

The Adaptable Deployable Entry and Placement Technology (ADEPT) project will be conducting the first flight test of ADEPT, titled Sounding Rocket One (SR-1), in just two months. The need for this flight test stems from the fact that ADEPT's supersonic dynamic stability has not yet been characterized. The SR-1 flight test will provide critical data describing the flight mechanics of ADEPT in ballistic flight. These data will feed decision making on future ADEPT mission designs. This presentation will describe the SR-1 scientific data products, possible flight test outcomes, and the implications of those outcomes on future ADEPT development. In addition, this presentation will describe free-flight ground testing performed in advance of the flight test. A subsonic flight dynamics test conducted at the Vertical Spin Tunnel located at NASA Langley Research Center provided subsonic flight dynamics data at high and low altitudes for multiple center of mass (CoM) locations. A ballistic range test at the Hypervelocity Free Flight Aerodynamics Facility (HFFAF) located at NASA Ames Research Center provided supersonic flight dynamics data at low supersonic Mach numbers. Execution and outcomes of these tests will be discussed. Finally, a hypothesized trajectory estimate for the SR-1 flight will be presented.

Flight control actuation system

Science.gov (United States)

Wingett, Paul T. (Inventor); Gaines, Louie T. (Inventor); Evans, Paul S. (Inventor); Kern, James I. (Inventor)

2006-01-01

A flight control actuation system comprises a controller, electromechanical actuator and a pneumatic actuator. During normal operation, only the electromechanical actuator is needed to operate a flight control surface. When the electromechanical actuator load level exceeds 40 amps positive, the controller activates the pneumatic actuator to offset electromechanical actuator loads to assist the manipulation of flight control surfaces. The assistance from the pneumatic load assist actuator enables the use of an electromechanical actuator that is smaller in size and mass, requires less power, needs less cooling processes, achieves high output forces and adapts to electrical current variations. The flight control actuation system is adapted for aircraft, spacecraft, missiles, and other flight vehicles, especially flight vehicles that are large in size and travel at high velocities.

Aurora Flight Sciences' Perseus B Remotely Piloted Aircraft in Flight

Science.gov (United States)

1998-01-01

A long, slender wing and a pusher propeller at the rear characterize the Perseus B remotely piloted research aircraft, seen here during a test flight in June 1998. Perseus B is a remotely piloted aircraft developed as a design-performance testbed under NASA's Environmental Research Aircraft and Sensor Technology (ERAST) project. Perseus is one of several flight vehicles involved in the ERAST project. A piston engine, propeller-powered aircraft, Perseus was designed and built by Aurora Flight Sciences Corporation, Manassas, Virginia. The objectives of Perseus B's ERAST flight tests have been to reach and maintain horizontal flight above altitudes of 60,000 feet and demonstrate the capability to fly missions lasting from 8 to 24 hours, depending on payload and altitude requirements. The Perseus B aircraft established an unofficial altitude record for a single-engine, propeller-driven, remotely piloted aircraft on June 27, 1998. It reached an altitude of 60,280 feet. In 1999, several modifications were made to the Perseus aircraft including engine, avionics, and flight-control-system improvements. These improvements were evaluated in a series of operational readiness and test missions at the Dryden Flight Research Center, Edwards, California. Perseus is a high-wing monoplane with a conventional tail design. Its narrow, straight, high-aspect-ratio wing is mounted atop the fuselage. The aircraft is pusher-designed with the propeller mounted in the rear. This design allows for interchangeable scientific-instrument payloads to be placed in the forward fuselage. The design also allows for unobstructed airflow to the sensors and other devices mounted in the payload compartment. The Perseus B that underwent test and development in 1999 was the third generation of the Perseus design, which began with the Perseus Proof-Of-Concept aircraft. Perseus was initially developed as part of NASA's Small High-Altitude Science Aircraft (SHASA) program, which later evolved into the ERAST

Flight Testing an Iced Business Jet for Flight Simulation Model Validation

Science.gov (United States)

Ratvasky, Thomas P.; Barnhart, Billy P.; Lee, Sam; Cooper, Jon

2007-01-01

A flight test of a business jet aircraft with various ice accretions was performed to obtain data to validate flight simulation models developed through wind tunnel tests. Three types of ice accretions were tested: pre-activation roughness, runback shapes that form downstream of the thermal wing ice protection system, and a wing ice protection system failure shape. The high fidelity flight simulation models of this business jet aircraft were validated using a software tool called "Overdrive." Through comparisons of flight-extracted aerodynamic forces and moments to simulation-predicted forces and moments, the simulation models were successfully validated. Only minor adjustments in the simulation database were required to obtain adequate match, signifying the process used to develop the simulation models was successful. The simulation models were implemented in the NASA Ice Contamination Effects Flight Training Device (ICEFTD) to enable company pilots to evaluate flight characteristics of the simulation models. By and large, the pilots confirmed good similarities in the flight characteristics when compared to the real airplane. However, pilots noted pitch up tendencies at stall with the flaps extended that were not representative of the airplane and identified some differences in pilot forces. The elevator hinge moment model and implementation of the control forces on the ICEFTD were identified as a driver in the pitch ups and control force issues, and will be an area for future work.

Flight research and testing

Science.gov (United States)

Putnam, Terrill W.; Ayers, Theodore G.

1989-01-01

Flight research and testing form a critical link in the aeronautic research and development chain. Brilliant concepts, elegant theories, and even sophisticated ground tests of flight vehicles are not sufficient to prove beyond a doubt that an unproven aeronautical concept will actually perform as predicted. Flight research and testing provide the ultimate proof that an idea or concept performs as expected. Ever since the Wright brothers, flight research and testing were the crucible in which aeronautical concepts were advanced and proven to the point that engineers and companies are willing to stake their future to produce and design aircraft. This is still true today, as shown by the development of the experimental X-30 aerospace plane. The Dryden Flight Research Center (Ames-Dryden) continues to be involved in a number of flight research programs that require understanding and characterization of the total airplane in all the aeronautical disciplines, for example the X-29. Other programs such as the F-14 variable-sweep transition flight experiment have focused on a single concept or discipline. Ames-Dryden also continues to conduct flight and ground based experiments to improve and expand the ability to test and evaluate advanced aeronautical concepts. A review of significant aeronautical flight research programs and experiments is presented to illustrate both the progress being made and the challenges to come.

14 CFR 25.865 - Fire protection of flight controls, engine mounts, and other flight structure.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Fire protection of flight controls, engine... Design and Construction Fire Protection § 25.865 Fire protection of flight controls, engine mounts, and other flight structure. Essential flight controls, engine mounts, and other flight structures located in...

L(sub 1) Adaptive Flight Control System: Flight Evaluation and Technology Transition

Science.gov (United States)

Xargay, Enric; Hovakimyan, Naira; Dobrokhodov, Vladimir; Kaminer, Isaac; Gregory, Irene M.; Cao, Chengyu

2010-01-01

Certification of adaptive control technologies for both manned and unmanned aircraft represent a major challenge for current Verification and Validation techniques. A (missing) key step towards flight certification of adaptive flight control systems is the definition and development of analysis tools and methods to support Verification and Validation for nonlinear systems, similar to the procedures currently used for linear systems. In this paper, we describe and demonstrate the advantages of L(sub l) adaptive control architectures for closing some of the gaps in certification of adaptive flight control systems, which may facilitate the transition of adaptive control into military and commercial aerospace applications. As illustrative examples, we present the results of a piloted simulation evaluation on the NASA AirSTAR flight test vehicle, and results of an extensive flight test program conducted by the Naval Postgraduate School to demonstrate the advantages of L(sub l) adaptive control as a verifiable robust adaptive flight control system.

Perseus Post-flight

Science.gov (United States)

1991-01-01

Crew members check out the Perseus proof-of-concept vehicle on Rogers Dry Lake, adjacent to the Dryden Flight Research Center, Edwards, California, after a test flight in 1991. Perseus B is a remotely piloted aircraft developed as a design-performance testbed under NASA's Environmental Research Aircraft and Sensor Technology (ERAST) project. Perseus is one of several flight vehicles involved in the ERAST project. A piston engine, propeller-powered aircraft, Perseus was designed and built by Aurora Flight Sciences Corporation, Manassas, Virginia. The objectives of Perseus B's ERAST flight tests have been to reach and maintain horizontal flight above altitudes of 60,000 feet and demonstrate the capability to fly missions lasting from 8 to 24 hours, depending on payload and altitude requirements. The Perseus B aircraft established an unofficial altitude record for a single-engine, propeller-driven, remotely piloted aircraft on June 27, 1998. It reached an altitude of 60,280 feet. In 1999, several modifications were made to the Perseus aircraft including engine, avionics, and flight-control-system improvements. These improvements were evaluated in a series of operational readiness and test missions at the Dryden Flight Research Center, Edwards, California. Perseus is a high-wing monoplane with a conventional tail design. Its narrow, straight, high-aspect-ratio wing is mounted atop the fuselage. The aircraft is pusher-designed with the propeller mounted in the rear. This design allows for interchangeable scientific-instrument payloads to be placed in the forward fuselage. The design also allows for unobstructed airflow to the sensors and other devices mounted in the payload compartment. The Perseus B that underwent test and development in 1999 was the third generation of the Perseus design, which began with the Perseus Proof-Of-Concept aircraft. Perseus was initially developed as part of NASA's Small High-Altitude Science Aircraft (SHASA) program, which later evolved

Wind and Wake Sensing with UAV Formation Flight: System Development and Flight Testing

Science.gov (United States)

Larrabee, Trenton Jameson

Wind turbulence including atmospheric turbulence and wake turbulence have been widely investigated; however, only recently it become possible to use Unmanned Aerial Vehicles (UAVs) as a validation tool for research in this area. Wind can be a major contributing factor of adverse weather for aircraft. More importantly, it is an even greater risk towards UAVs because of their small size and weight. Being able to estimate wind fields and gusts can potentially provide substantial benefits for both unmanned and manned aviation. Possible applications include gust suppression for improving handling qualities, a better warning system for high wind encounters, and enhanced control for small UAVs during flight. On the other hand, the existence of wind can be advantageous since it can lead to fuel savings and longer duration flights through dynamic soaring or thermal soaring. Wakes are an effect of the lift distribution across an aircraft's wing or tail. Wakes can cause substantial disturbances when multiple aircraft are moving through the same airspace. In fact, the perils from an aircraft flying through the wake of another aircraft is a leading cause of the delay between takeoff times at airports. Similar to wind, though, wakes can be useful for energy harvesting and increasing an aircraft's endurance when flying in formation which can be a great advantage to UAVs because they are often limited in flight time due to small payload capacity. Formation flight can most often be seen in manned aircraft but can be adopted for use with unmanned systems. Autonomous flight is needed for flying in the "sweet spot" of the generated wakes for energy harvesting as well as for thermal soaring during long duration flights. For the research presented here formation flight was implemented for the study of wake sensing and gust alleviation. The major contributions of this research are in the areas of a novel technique to estimate wind using an Unscented Kalman filter and experimental wake

X-43A Flight Controls

Science.gov (United States)

Baumann, Ethan

2006-01-01

A viewgraph presentation detailing X-43A Flight controls at NASA Dryden Flight Research Center is shown. The topics include: 1) NASA Dryden, Overview and current and recent flight test programs; 2) Unmanned Aerial Vehicle Synthetic Aperture Radar (UAVSAR) Program, Program Overview and Platform Precision Autopilot; and 3) Hyper-X Program, Program Overview, X-43A Flight Controls and Flight Results.

F-16XL ship #1 (#849) during first flight of the Digital Flight Control System (DFCS)

Science.gov (United States)

1997-01-01

After completing its first flight with the Digital Flight Control System on December 16, 1997, the F-16XL #1 aircraft began a series of envelope expansion flights. On January 27 and 29, 1998, it successfully completed structural clearance tests, as well as most of the load testing Only flights at Mach 1.05 at 10,000 feet, Mach 1.1 at 15,000 feet, and Mach 1.2 at 20,000 feet remained. During the next flight, on February 4, an instrumentation problem cut short the planned envelope expansion tests. After the problem was corrected, the F-16XL returned to flight status, and on February 18 and 20, flight control and evaluation flights were made. Two more research flights were planned for the following week, but another problem appeared. During the ground start up, project personnel noticed that the leading edge flap moved without being commanded. The Digital Flight Control Computer was sent to the Lockheed-Martin facility at Fort Worth, where the problem was traced to a defective chip in the computer. After it was replaced, the F-16XL #1 flew a highly successful flight controls and handling qualities evaluation flight on March 26, clearing the way for the final tests. The final limited loads expansion flight occurred on March 31, and was fully successful. As a result, the on-site Lockheed-Martin loads engineer cleared the aircraft to Mach 1.8. The remaining two handling qualities and flight control evaluation flights were both made on April 3, 1998. These three flights concluded the flight test portion of the DFCS upgrade.

DAST in Flight

Science.gov (United States)

1980-01-01

The modified BQM-34 Firebee II drone with Aeroelastic Research Wing (ARW-1), a supercritical airfoil, during a 1980 research flight. The remotely-piloted vehicle, which was air launched from NASA's NB-52B mothership, participated in the Drones for Aerodynamic and Structural Testing (DAST) program which ran from 1977 to 1983. The DAST 1 aircraft (Serial #72-1557), pictured, crashed on 12 June 1980 after its right wing ripped off during a test flight near Cuddeback Dry Lake, California. The crash occurred on the modified drone's third free flight. These are the image contact sheets for each image resolution of the NASA Dryden Drones for Aerodynamic and Structural Testing (DAST) Photo Gallery. From 1977 to 1983, the Dryden Flight Research Center, Edwards, California, (under two different names) conducted the DAST Program as a high-risk flight experiment using a ground-controlled, pilotless aircraft. Described by NASA engineers as a 'wind tunnel in the sky,' the DAST was a specially modified Teledyne-Ryan BQM-34E/F Firebee II supersonic target drone that was flown to validate theoretical predictions under actual flight conditions in a joint project with the Langley Research Center, Hampton, Virginia. The DAST Program merged advances in electronic remote control systems with advances in airplane design. Drones (remotely controlled, missile-like vehicles initially developed to serve as gunnery targets) had been deployed successfully during the Vietnamese conflict as reconnaissance aircraft. After the war, the energy crisis of the 1970s led NASA to seek new ways to cut fuel use and improve airplane efficiency. The DAST Program's drones provided an economical, fuel-conscious method for conducting in-flight experiments from a remote ground site. DAST explored the technology required to build wing structures with less than normal stiffness. This was done because stiffness requires structural weight but ensures freedom from flutter-an uncontrolled, divergent oscillation of

Flapping wing flight can save aerodynamic power compared to steady flight.

Science.gov (United States)

Pesavento, Umberto; Wang, Z Jane

2009-09-11

Flapping flight is more maneuverable than steady flight. It is debated whether this advantage is necessarily accompanied by a trade-off in the flight efficiency. Here we ask if any flapping motion exists that is aerodynamically more efficient than the optimal steady motion. We solve the Navier-Stokes equation governing the fluid dynamics around a 2D flapping wing, and determine the minimal aerodynamic power needed to support a specified weight. While most flapping wing motions are more costly than the optimal steady wing motion, we find that optimized flapping wing motions can save up to 27% of the aerodynamic power required by the optimal steady flight. We explain the cause of this energetic advantage.

Flight code validation simulator

Science.gov (United States)

Sims, Brent A.

1996-05-01

An End-To-End Simulation capability for software development and validation of missile flight software on the actual embedded computer has been developed utilizing a 486 PC, i860 DSP coprocessor, embedded flight computer and custom dual port memory interface hardware. This system allows real-time interrupt driven embedded flight software development and checkout. The flight software runs in a Sandia Digital Airborne Computer and reads and writes actual hardware sensor locations in which Inertial Measurement Unit data resides. The simulator provides six degree of freedom real-time dynamic simulation, accurate real-time discrete sensor data and acts on commands and discretes from the flight computer. This system was utilized in the development and validation of the successful premier flight of the Digital Miniature Attitude Reference System in January of 1995 at the White Sands Missile Range on a two stage attitude controlled sounding rocket.

Perseus in Flight

Science.gov (United States)

1991-01-01

The Perseus proof-of-concept vehicle flies over Rogers Dry Lake at the Dryden Flight Research Center, Edwards, California, to test basic design concepts for the remotely-piloted, high-altitude vehicle. Perseus B is a remotely piloted aircraft developed as a design-performance testbed under NASA's Environmental Research Aircraft and Sensor Technology (ERAST) project. Perseus is one of several flight vehicles involved in the ERAST project. A piston engine, propeller-powered aircraft, Perseus was designed and built by Aurora Flight Sciences Corporation, Manassas, Virginia. The objectives of Perseus B's ERAST flight tests have been to reach and maintain horizontal flight above altitudes of 60,000 feet and demonstrate the capability to fly missions lasting from 8 to 24 hours, depending on payload and altitude requirements. The Perseus B aircraft established an unofficial altitude record for a single-engine, propeller-driven, remotely piloted aircraft on June 27, 1998. It reached an altitude of 60,280 feet. In 1999, several modifications were made to the Perseus aircraft including engine, avionics, and flight-control-system improvements. These improvements were evaluated in a series of operational readiness and test missions at the Dryden Flight Research Center, Edwards, California. Perseus is a high-wing monoplane with a conventional tail design. Its narrow, straight, high-aspect-ratio wing is mounted atop the fuselage. The aircraft is pusher-designed with the propeller mounted in the rear. This design allows for interchangeable scientific-instrument payloads to be placed in the forward fuselage. The design also allows for unobstructed airflow to the sensors and other devices mounted in the payload compartment. The Perseus B that underwent test and development in 1999 was the third generation of the Perseus design, which began with the Perseus Proof-Of-Concept aircraft. Perseus was initially developed as part of NASA's Small High-Altitude Science Aircraft (SHASA

Orion Exploration Flight Test Post-Flight Inspection and Analysis

Science.gov (United States)

Miller, J. E.; Berger, E. L.; Bohl, W. E.; Christiansen, E. L.; Davis, B. A.; Deighton, K. D.; Enriquez, P. A.; Garcia, M. A.; Hyde, J. L.; Oliveras, O. M.

2017-01-01

The principal mechanism for developing orbital debris environment models, is to make observations of larger pieces of debris in the range of several centimeters and greater using radar and optical techniques. For particles that are smaller than this threshold, breakup and migration models of particles to returned surfaces in lower orbit are relied upon to quantify the flux. This reliance on models to derive spatial densities of particles that are of critical importance to spacecraft make the unique nature of the EFT-1's return surface a valuable metric. To this end detailed post-flight inspections have been performed of the returned EFT-1 backshell, and the inspections identified six candidate impact sites that were not present during the pre-flight inspections. This paper describes the post-flight analysis efforts to characterize the EFT-1 mission craters. This effort included ground based testing to understand small particle impact craters in the thermal protection material, the pre- and post-flight inspection, the crater analysis using optical, X-ray computed tomography (CT) and scanning electron microscope (SEM) techniques, and numerical simulations.

Capital Flight and Economic Performance

OpenAIRE

Beja, Edsel Jr.

2007-01-01

Capital flight aggravates resource constraints and contributes to undermine long-term economic growth. Counterfactual calculations on the Philippines suggest that capital flight contributed to lower the quality of long-term economic growth. Sustained capital flight over three decades means that capital flight had a role for the Philippines to lose the opportunities to achieve economic takeoff. Unless decisive policy actions are taken up to address enduring capital flight and manage the macroe...

Recent estimates of capital flight

OpenAIRE

Claessens, Stijn; Naude, David

1993-01-01

Researchers and policymakers have in recent years paid considerable attention to the phenomenon of capital flight. Researchers have focused on four questions: What concept should be used to measure capital flight? What figure for capital flight will emerge, using this measure? Can the occurrence and magnitude of capital flight be explained by certain (economic) variables? What policy changes can be useful to reverse capital flight? The authors focus strictly on presenting estimates of capital...

The relationship of certified flight instructors' emotional intelligence levels on flight student advancement

Science.gov (United States)

Hokeness, Mark Merrill

Aviation researchers estimate airline companies will require nearly 500,000 pilots in the next 20 years. The role of a Certified Flight Instructor (CFI) is to move student pilots to professional pilots with training typically conducted in one-on-one student and instructor sessions. The knowledge of aviation, professionalism as a teacher, and the CFI’s interpersonal skills can directly affect the successes and advancement of a student pilot. A new and emerging assessment of people skills is known as emotional intelligence (EI). The EI of the CFI can and will affect a flight students’ learning experiences. With knowledge of emotional intelligence and its effect on flight training, student pilot dropouts from aviation may be reduced, thus helping to ensure an adequate supply of pilots. Without pilots, the growth of the commercial aviation industry will be restricted. This mixed method research study established the correlation between a CFI’s measured EI levels and the advancement of flight students. The elements contributing to a CFI’s EI level were not found to be teaching or flight-related experiences, suggesting other life factors are drawn upon by the CFI and are reflected in their emotional intelligence levels presented to flight students. Students respond positively to CFIs with higher levels of emotional intelligence. Awareness of EI skills by both the CFI and flight student contribute to flight student successes and advancement.

Insect flight muscle metabolism

NARCIS (Netherlands)

Horst, D.J. van der; Beenakkers, A.M.Th.; Marrewijk, W.J.A. van

1984-01-01

The flight of an insect is of a very complicated and extremely energy-demanding nature. Wingbeat frequency may differ between various species but values up to 1000 Hz have been measured. Consequently metabolic activity may be very high during flight and the transition from rest to flight is

14 CFR 63.23 - Special purpose flight engineer and flight navigator certificates: Operation of U.S.-registered...

Science.gov (United States)

2010-01-01

... purpose flight engineer and flight navigator certificates: Operation of U.S.-registered civil airplanes... flight engineer or flight navigator duties on a civil airplane of U.S. registry, leased to a person not a... certificate holder is performing flight engineer or flight navigator duties on the U.S.-registered civil...

14 CFR 23.865 - Fire protection of flight controls, engine mounts, and other flight structure.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Fire protection of flight controls, engine... controls, engine mounts, and other flight structure. Flight controls, engine mounts, and other flight... they are capable of withstanding the effects of a fire. Engine vibration isolators must incorporate...

Navigation and flight director guidance for the NASA/FAA helicopter MLS curved approach flight test program

Science.gov (United States)

Phatak, A. V.; Lee, M. G.

1985-01-01

The navigation and flight director guidance systems implemented in the NASA/FAA helicopter microwave landing system (MLS) curved approach flight test program is described. Flight test were conducted at the U.S. Navy's Crows Landing facility, using the NASA Ames UH-lH helicopter equipped with the V/STOLAND avionics system. The purpose of these tests was to investigate the feasibility of flying complex, curved and descending approaches to a landing using MLS flight director guidance. A description of the navigation aids used, the avionics system, cockpit instrumentation and on-board navigation equipment used for the flight test is provided. Three generic reference flight paths were developed and flown during the test. They were as follows: U-Turn, S-turn and Straight-In flight profiles. These profiles and their geometries are described in detail. A 3-cue flight director was implemented on the helicopter. A description of the formulation and implementation of the flight director laws is also presented. Performance data and analysis is presented for one pilot conducting the flight director approaches.

Perfect discretization of path integrals

International Nuclear Information System (INIS)

Steinhaus, Sebastian

2012-01-01

In order to obtain a well-defined path integral one often employs discretizations. In the case of General Relativity these generically break diffeomorphism symmetry, which has severe consequences since these symmetries determine the dynamics of the corresponding system. In this article we consider the path integral of reparametrization invariant systems as a toy example and present an improvement procedure for the discretized propagator. Fixed points and convergence of the procedure are discussed. Furthermore we show that a reparametrization invariant path integral implies discretization independence and acts as a projector onto physical states.

Perfect discretization of path integrals

Science.gov (United States)

Steinhaus, Sebastian

2012-05-01

In order to obtain a well-defined path integral one often employs discretizations. In the case of General Relativity these generically break diffeomorphism symmetry, which has severe consequences since these symmetries determine the dynamics of the corresponding system. In this article we consider the path integral of reparametrization invariant systems as a toy example and present an improvement procedure for the discretized propagator. Fixed points and convergence of the procedure are discussed. Furthermore we show that a reparametrization invariant path integral implies discretization independence and acts as a projector onto physical states.

Apollo experience report: Development flight instrumentation. [telemetry equipment for space flight test program

Science.gov (United States)

Farmer, N. B.

1974-01-01

Development flight instrumentation was delivered for 25 Apollo vehicles as Government-furnished equipment. The problems and philosophies of an activity that was concerned with supplying telemetry equipment to a space-flight test program are discussed. Equipment delivery dates, system-design details, and flight-performance information for each mission also are included.

IRVE-II Post-Flight Trajectory Reconstruction

Science.gov (United States)

O'Keefe, Stephen A.; Bose, David M.

2010-01-01

NASA s Inflatable Re-entry Vehicle Experiment (IRVE) II successfully demonstrated an inflatable aerodynamic decelerator after being launched aboard a sounding rocket from Wallops Flight Facility (WFF). Preliminary day of flight data compared well with pre-flight Monte Carlo analysis, and a more complete trajectory reconstruction performed with an Extended Kalman Filter (EKF) approach followed. The reconstructed trajectory and comparisons to an attitude solution provided by NASA Sounding Rocket Operations Contract (NSROC) personnel at WFF are presented. Additional comparisons are made between the reconstructed trajectory and pre and post-flight Monte Carlo trajectory predictions. Alternative observations of the trajectory are summarized which leverage flight accelerometer measurements, the pre-flight aerodynamic database, and on-board flight video. Finally, analysis of the payload separation and aeroshell deployment events are presented. The flight trajectory is reconstructed to fidelity sufficient to assess overall project objectives related to flight dynamics and overall, IRVE-II flight dynamics are in line with expectations

Flight Tasks and Metrics to Evaluate Laser Eye Protection in Flight Simulators

Science.gov (United States)

2017-07-07

IFR ) IFR Instrument Flight Rules LED Light Emitting Diode LEP Laser Eye Protection MAPP Model Assessing Pilot Performance OD Optical Density...LEP and then use them to assess the impact of wearing LEP in a flight simulator environment. 2 Pending Distribution, A: Approved for public...2005). LEP has the potential to alter distinct characteristics of the visual environment, giving rise to concerns over the impact on flight tasks and

IceBridge Mission Flight Reports

Data.gov (United States)

National Aeronautics and Space Administration — The IceBridge Mission Flight Reports data set contains flight reports from NASA Operation IceBridge Greenland, Arctic, Antarctic, and Alaska missions. Flight reports...

Integrated flight path planning system and flight control system for unmanned helicopters.

Science.gov (United States)

Jan, Shau Shiun; Lin, Yu Hsiang

2011-01-01

This paper focuses on the design of an integrated navigation and guidance system for unmanned helicopters. The integrated navigation system comprises two systems: the Flight Path Planning System (FPPS) and the Flight Control System (FCS). The FPPS finds the shortest flight path by the A-Star (A*) algorithm in an adaptive manner for different flight conditions, and the FPPS can add a forbidden zone to stop the unmanned helicopter from crossing over into dangerous areas. In this paper, the FPPS computation time is reduced by the multi-resolution scheme, and the flight path quality is improved by the path smoothing methods. Meanwhile, the FCS includes the fuzzy inference systems (FISs) based on the fuzzy logic. By using expert knowledge and experience to train the FIS, the controller can operate the unmanned helicopter without dynamic models. The integrated system of the FPPS and the FCS is aimed at providing navigation and guidance to the mission destination and it is implemented by coupling the flight simulation software, X-Plane, and the computing software, MATLAB. Simulations are performed and shown in real time three-dimensional animations. Finally, the integrated system is demonstrated to work successfully in controlling the unmanned helicopter to operate in various terrains of a digital elevation model (DEM).

Integrated Flight Path Planning System and Flight Control System for Unmanned Helicopters

Science.gov (United States)

Jan, Shau Shiun; Lin, Yu Hsiang

2011-01-01

This paper focuses on the design of an integrated navigation and guidance system for unmanned helicopters. The integrated navigation system comprises two systems: the Flight Path Planning System (FPPS) and the Flight Control System (FCS). The FPPS finds the shortest flight path by the A-Star (A*) algorithm in an adaptive manner for different flight conditions, and the FPPS can add a forbidden zone to stop the unmanned helicopter from crossing over into dangerous areas. In this paper, the FPPS computation time is reduced by the multi-resolution scheme, and the flight path quality is improved by the path smoothing methods. Meanwhile, the FCS includes the fuzzy inference systems (FISs) based on the fuzzy logic. By using expert knowledge and experience to train the FIS, the controller can operate the unmanned helicopter without dynamic models. The integrated system of the FPPS and the FCS is aimed at providing navigation and guidance to the mission destination and it is implemented by coupling the flight simulation software, X-Plane, and the computing software, MATLAB. Simulations are performed and shown in real time three-dimensional animations. Finally, the integrated system is demonstrated to work successfully in controlling the unmanned helicopter to operate in various terrains of a digital elevation model (DEM). PMID:22164029

Eclipse takeoff and flight

Science.gov (United States)

1998-01-01

This 25-second clip shows the QF-106 'Delta Dart' tethered to the USAF C-141A during takeoff and in flight. NASA Dryden Flight Research Center, Edwards, California, supported a Kelly Space and Technology, Inc. (KST)/U.S. Air Force project known as Eclipse, which demonstrated a reusable tow launch vehicle concept. The purpose of the project was to demonstrate a reusable tow launch vehicle concept that had been conceived and patented by KST. Kelly Space obtained a contract with the USAF Research Laboratory for the tow launch demonstration project under the Small Business Innovation Research (SBIR) program. The USAF SBIR contract included the modifications to turn the QF-106 into the Experimental Demonstrator #1 (EXD-01), and the C141A aircraft to incorporate the tow provisions to link the two aircraft, as well as conducting flight tests. The demonstration consisted of ground and flight tests. These tests included a Combined Systems Test of both airplanes joined by a tow rope, a towed taxi test, and six towed flights. The primary goal of the project was demonstrating the tow phase of the Eclipse concept using a scaled-down tow aircraft (C-141A) and a representative aerodynamically-shaped aircraft (QF-106A) as a launch vehicle. This was successfully accomplished. On December 20, 1997, NASA research pilot Mark Stucky flew a QF-106 on the first towed flight behind an Air Force C-141 in the joint Eclipse project with KST to demonstrate the reusable tow launch vehicle concept developed by KST. Kelly hoped to use the data from the tow tests to validate a tow-to-launch procedure for reusable space launch vehicles. Stucky flew six successful tow tests between December 1997 and February 6, 1998. On February 6, 1998, the sixth and final towed flight brought the project to a successful completion. Preliminary flight results determined that the handling qualities of the QF-106 on tow were very stable; actual flight measured values of tow rope tension were well within predictions

The flights before the flight - An overview of shuttle astronaut training

Science.gov (United States)

Sims, John T.; Sterling, Michael R.

1989-01-01

Space shuttle astronaut training is centered at NASA's Johnson Space Center in Houston, Texas. Each astronaut receives many different types of training from many sources. This training includes simulator training in the Shuttle Mission Simulator, in-flight simulator training in the Shuttle Training Aircraft, Extravehicular Activity training in the Weightless Environment Training Facility and a variety of lectures and briefings. Once the training program is completed each shuttle flight crew is well-prepared to perform the normal operations required for their flight and deal with any shuttle system malfunctions that might occur.

Implementation and flight tests for the Digital Integrated Automatic Landing System (DIALS). Part 1: Flight software equations, flight test description and selected flight test data

Science.gov (United States)

Hueschen, R. M.

1986-01-01

Five flight tests of the Digital Automated Landing System (DIALS) were conducted on the Advanced Transport Operating Systems (ATOPS) Transportation Research Vehicle (TSRV) -- a modified Boeing 737 aircraft for advanced controls and displays research. These flight tests were conducted at NASA's Wallops Flight Center using the microwave landing system (MLS) installation on runway 22. This report describes the flight software equations of the DIALS which was designed using modern control theory direct-digital design methods and employed a constant gain Kalman filter. Selected flight test performance data is presented for localizer (runway centerline) capture and track at various intercept angles, for glideslope capture and track of 3, 4.5, and 5 degree glideslopes, for the decrab maneuver, and for the flare maneuver. Data is also presented to illustrate the system performance in the presence of cross, gust, and shear winds. The mean and standard deviation of the peak position errors for localizer capture were, respectively, 24 feet and 26 feet. For mild wind conditions, glideslope and localizer tracking position errors did not exceed, respectively, 5 and 20 feet. For gusty wind conditions (8 to 10 knots), these errors were, respectively, 10 and 30 feet. Ten hands off automatic lands were performed. The standard deviation of the touchdown position and velocity errors from the mean values were, respectively, 244 feet and 0.7 feet/sec.

Theseus Landing Following Maiden Flight

Science.gov (United States)

1996-01-01

The Theseus prototype research aircraft shows off its high aspect-ratio wing as it comes in for a landing on Rogers Dry Lake after its first test flight from NASA's Dryden Flight Research Center, Edwards, California, on May 24, 1996. The Theseus aircraft, built and operated by Aurora Flight Sciences Corporation, Manassas, Virginia, was a unique aircraft flown at NASA's Dryden Flight Research Center, Edwards, California, under a cooperative agreement between NASA and Aurora. Dryden hosted the Theseus program, providing hangar space and range safety for flight testing. Aurora Flight Sciences was responsible for the actual flight testing, vehicle flight safety, and operation of the aircraft. The Theseus remotely piloted aircraft flew its maiden flight on May 24, 1996, at Dryden. During its sixth flight on November 12, 1996, Theseus experienced an in-flight structural failure that resulted in the loss of the aircraft. As of the beginning of the year 2000, Aurora had not rebuilt the aircraft. Theseus was built for NASA under an innovative, $4.9 million fixed-price contract by Aurora Flight Sciences Corporation and its partners, West Virginia University, Morgantown, West Virginia, and Fairmont State College, Fairmont, West Virginia. The twin-engine, unpiloted vehicle had a 140-foot wingspan, and was constructed largely of composite materials. Powered by two 80-horsepower, turbocharged piston engines that drove twin 9-foot-diameter propellers, Theseus was designed to fly autonomously at high altitudes, with takeoff and landing under the active control of a ground-based pilot in a ground control station 'cockpit.' With the potential ability to carry 700 pounds of science instruments to altitudes above 60,000 feet for durations of greater than 24 hours, Theseus was intended to support research in areas such as stratospheric ozone depletion and the atmospheric effects of future high-speed civil transport aircraft engines. Instruments carried aboard Theseus also would be able

X-36 in Flight over Mojave Desert during 5th Flight

Science.gov (United States)

1997-01-01

The unusual lines of the X-36 Tailless Fighter Agility Research Aircraft contrast sharply with the desert floor as the remotely-piloted aircraft flies over the Mojave Desert on a June 1997 research flight. The NASA/Boeing X-36 Tailless Fighter Agility Research Aircraft program successfully demonstrated the tailless fighter design using advanced technologies to improve the maneuverability and survivability of possible future fighter aircraft. The program met or exceeded all project goals. For 31 flights during 1997 at the Dryden Flight Research Center, Edwards, California, the project team examined the aircraft's agility at low speed / high angles of attack and at high speed / low angles of attack. The aircraft's speed envelope reached up to 206 knots (234 mph). This aircraft was very stable and maneuverable. It handled very well. The X-36 vehicle was designed to fly without the traditional tail surfaces common on most aircraft. Instead, a canard forward of the wing was used as well as split ailerons and an advanced thrust-vectoring nozzle for directional control. The X-36 was unstable in both pitch and yaw axes, so an advanced, single-channel digital fly-by-wire control system (developed with some commercially available components) was put in place to stabilize the aircraft. Using a video camera mounted in the nose of the aircraft and an onboard microphone, the X-36 was remotely controlled by a pilot in a ground station virtual cockpit. A standard fighter-type head-up display (HUD) and a moving-map representation of the vehicle's position within the range in which it flew provided excellent situational awareness for the pilot. This pilot-in-the-loop approach eliminated the need for expensive and complex autonomous flight control systems and the risks associated with their inability to deal with unknown or unforeseen phenomena in flight. Fully fueled the X-36 prototype weighed approximately 1,250 pounds. It was 19 feet long and three feet high with a wingspan of

In-flight sleep, pilot fatigue and Psychomotor Vigilance Task performance on ultra-long range versus long range flights.

Science.gov (United States)

Gander, Philippa H; Signal, T Leigh; van den Berg, Margo J; Mulrine, Hannah M; Jay, Sarah M; Jim Mangie, Captain

2013-12-01

This study evaluated whether pilot fatigue was greater on ultra-long range (ULR) trips (flights >16 h on 10% of trips in a 90-day period) than on long range (LR) trips. The within-subjects design controlled for crew complement, pattern of in-flight breaks, flight direction and departure time. Thirty male Captains (mean age = 54.5 years) and 40 male First officers (mean age = 48.0 years) were monitored on commercial passenger flights (Boeing 777 aircraft). Sleep was monitored (actigraphy, duty/sleep diaries) from 3 days before the first study trip to 3 days after the second study trip. Karolinska Sleepiness Scale, Samn-Perelli fatigue ratings and a 5-min Psychomotor Vigilance Task were completed before, during and after every flight. Total sleep in the 24 h before outbound flights and before inbound flights after 2-day layovers was comparable for ULR and LR flights. All pilots slept on all flights. For each additional hour of flight time, they obtained an estimated additional 12.3 min of sleep. Estimated mean total sleep was longer on ULR flights (3 h 53 min) than LR flights (3 h 15 min; P(F) = 0.0004). Sleepiness ratings were lower and mean reaction speed was faster at the end of ULR flights. Findings suggest that additional in-flight sleep mitigated fatigue effectively on longer flights. Further research is needed to clarify the contributions to fatigue of in-flight sleep versus time awake at top of descent. The study design was limited to eastward outbound flights with two Captains and two First Officers. Caution must be exercised when extrapolating to different operations. © 2013 European Sleep Research Society.

Shoemaker-Levy 9/JUPITER Collision Update

Science.gov (United States)

1994-05-01

There are many signs that the upcoming collision between comet Shoemaker-Levy 9 and giant planet Jupiter is beginning to catch the imagination of the public. Numerous reports in the various media describe the effects expected during this unique event which according to the latest calculations will start in the evening of July 16 and end in the morning of July 22, 1994. (The times in this Press Release are given in Central European Summer Time (CEST), i.e., Universal Time (UT) + 2 hours. The corresponding local time in Chile is CEST - 6 hours.) Astronomers all over the world are now preparing to observe the associated phenomena with virtually all major telescopes. There will be no less than 12 different investigations at the ESO La Silla observatory during this period. This Press Release updates the information published in ESO PR 02/94 (27 January 1994) and provides details about the special services which will be provided by ESO to the media around this rare astronomical event. SCIENTIFIC EXPECTATIONS The nucleus of comet Shoemaker-Levy 9 broke into many smaller pieces during a near passage of Jupiter in July 1992. They are now moving in parallel orbits around this planet and recent calculations show with close to 100 % certainty that they will all collide with it, just two months from now. At some time, more than 20 individual nuclei were observed. This Press Release is accompanied by a photo that shows this formation, the famous "string of pearls", as it looked like in early May 1994. Both Jupiter and these nuclei have been extensively observed during the past months. A large, coordinated observing programme at La Silla has been active since early April and the first results have become available. However, while we now possess more accurate information about the comet's motion and the times of impact, there is still great uncertainty about the effects which may actually be observed at the time of the impacts. This is first of all due to the fact that it has not

The Orion Exploration Flight Test Post Flight Solid Particle Flight Environment Inspection and Analysis

Science.gov (United States)

Miller, Joshua E.

2016-01-01

Orbital debris in the millimeter size range can pose a hazard to current and planned spacecraft due to the high relative impact speeds in Earth orbit. Fortunately, orbital debris has a relatively short life at lower altitudes due to atmospheric effects; however, at higher altitudes orbital debris can survive much longer and has resulted in a band of high flux around 700 to 1,500 km above the surface of the Earth. While large orbital debris objects are tracked via ground based observation, little information can be gathered about small particles except by returned surfaces, which until the Orion Exploration Flight Test number one (EFT-1), has only been possible for lower altitudes (400 to 500 km). The EFT-1 crew module backshell, which used a porous, ceramic tile system with surface coatings, has been inspected post-flight for potential micrometeoroid and orbital debris (MMOD) damage. This paper describes the pre- and post-flight activities of inspection, identification and analysis of six candidate MMOD impact craters from the EFT-1 mission.

Manned Flight Simulator (MFS)

Data.gov (United States)

Federal Laboratory Consortium — The Aircraft Simulation Division, home to the Manned Flight Simulator (MFS), provides real-time, high fidelity, hardware-in-the-loop flight simulation capabilities...

NASA/FAA/NCAR Supercooled Large Droplet Icing Flight Research: Summary of Winter 1996-1997 Flight Operations

Science.gov (United States)

Miller, Dean; Ratvasky, Thomas; Bernstein, Ben; McDonough, Frank; Strapp, J. Walter

1998-01-01

During the winter of 1996-1997, a flight research program was conducted at the NASA-Lewis Research Center to study the characteristics of Supercooled Large Droplets (SLD) within the Great Lakes region. This flight program was a joint effort between the National Aeronautics and Space Administration (NASA), the National Center for Atmospheric Research (NCAR), and the Federal Aviation Administration (FAA). Based on weather forecasts and real-time in-flight guidance provided by NCAR, the NASA-Lewis Icing Research Aircraft was flown to locations where conditions were believed to be conducive to the formation of Supercooled Large Droplets aloft. Onboard instrumentation was then used to record meteorological, ice accretion, and aero-performance characteristics encountered during the flight. A total of 29 icing research flights were conducted, during which "conventional" small droplet icing, SLD, and mixed phase conditions were encountered aloft. This paper will describe how flight operations were conducted, provide an operational summary of the flights, present selected experimental results from one typical research flight, and conclude with practical "lessons learned" from this first year of operation.

In-flight Assessment of Lower Body Negative Pressure as a Countermeasure for Post-flight Orthostatic Intolerance

Science.gov (United States)

Charles, J. B.; Stenger, M. B.; Phillips, T. R.; Arzeno, N. M.; Lee, S. M. C.

2009-01-01

Introduction. We investigated the efficacy of combining fluid loading with sustained lower body negative pressure (LBNP) to reverse orthostatic intolerance associated with weightlessness during and immediately after Space Shuttle missions. Methods. Shuttle astronauts (n=13) underwent 4 hours of LBNP at -30 mm(Hg) and ingested water and salt ( soak treatment) during flight in two complementary studies. In the first study (n=8), pre-flight heart rate (HR) and blood pressure (BP) responses to an LBNP ramp (5-min stages of -10 mm(Hg) steps to -50 mm(Hg) were compared to responses in-flight one and two days after LBNP soak treatment. In the second study (n=5), the soak was performed 24 hr before landing, and post-flight stand test results of soak subjects were compared with those of an untreated cohort (n=7). In both studies, the soak was scheduled late in the mission and was preceded by LBNP ramp tests at approximately 3-day intervals to document the in-flight loss of orthostatic tolerance. Results. Increased HR and decreased BP responses to LBNP were evident early in-flight. In-flight, one day after LBNP soak, HR and BP responses to LBNP were not different from pre-flight, but the effect was absent the second day after treatment. Post-flight there were no between-group differences in HR and BP responses to standing, but all 5 treatment subjects completed the 5-minute stand test whereas 2 of 7 untreated cohort subjects did not. Discussion. Exaggerated HR and BP responses to LBNP were evident within the first few days of space flight, extending results from Skylab. The combined LBNP and fluid ingestion countermeasure restored in-flight LBNP HR and BP responses to pre-flight levels and provided protection of post-landing orthostatic function. Unfortunately, any benefits of the combined countermeasure were offset by the complexity of its implementation, making it inappropriate for routine application during Shuttle flights.

Vision based flight procedure stereo display system

Science.gov (United States)

Shen, Xiaoyun; Wan, Di; Ma, Lan; He, Yuncheng

2008-03-01

A virtual reality flight procedure vision system is introduced in this paper. The digital flight map database is established based on the Geographic Information System (GIS) and high definitions satellite remote sensing photos. The flight approaching area database is established through computer 3D modeling system and GIS. The area texture is generated from the remote sensing photos and aerial photographs in various level of detail. According to the flight approaching procedure, the flight navigation information is linked to the database. The flight approaching area vision can be dynamic displayed according to the designed flight procedure. The flight approaching area images are rendered in 2 channels, one for left eye images and the others for right eye images. Through the polarized stereoscopic projection system, the pilots and aircrew can get the vivid 3D vision of the flight destination approaching area. Take the use of this system in pilots preflight preparation procedure, the aircrew can get more vivid information along the flight destination approaching area. This system can improve the aviator's self-confidence before he carries out the flight mission, accordingly, the flight safety is improved. This system is also useful in validate the visual flight procedure design, and it helps to the flight procedure design.

Review on flight simulators (today and tomorrow); Flight simulatior no genjo to kongo

Energy Technology Data Exchange (ETDEWEB)

Komura, T. [Mitsubishi Precision Company Limited, Tokyo (Japan)

2000-04-05

This paper presents various flight simulators. A flight simulator is classified into that for R and D on aircraft and that for flight training according to its usage. As an example of the former, the general-purpose flight simulation test facility of National Aerospace Laboratory, Science and Technology Agency is in use for development of the STOL experimental aircraft 'Asuka' and simulation experiments for space development. A civil aircraft simulator simulating the interior of a cockpit, operation feeling of piloting devices, flight performance, dynamic characteristics, an engine system and a hydraulic system like a real aircraft is in wide use for training pilots. A fighter simulator for air force is used for training detection of enemy's aircraft by radar, and missile shooting. An antisubmarine patrol aircraft simulator is used for training detection of submarines by sonic detector and magnetic detector, and torpedo air-launching. For both simulators, real simulation of detection sensors or battle environment is required. (NEDO)

Flight Muscle Dimorphism and Heterogeneity in Flight Initiation of Field-Collected Triatoma infestans (Hemiptera: Reduviidae)

OpenAIRE

Gurevitz, Juan M.; Kitron, Uriel; Gürtler, Ricardo E.

2007-01-01

Recent experiments demonstrated that most field-collected Triatoma infestans (Klug) (Hemiptera: Reduviidae) adults from northern Argentina either never initiated flight or did so repeatedly in both sexes. This pattern could not be explained by sex, adult age, weight, weight-to-length ratio (W/L), or chance. We examined whether bugs that never initiated flight possessed developed flight muscles, and whether flight muscle mass relative to total body mass (FMR) was related to the probability of ...

14 CFR 27.151 - Flight controls.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Flight controls. 27.151 Section 27.151... STANDARDS: NORMAL CATEGORY ROTORCRAFT Flight Flight Characteristics § 27.151 Flight controls. (a) Longitudinal, lateral, directional, and collective controls may not exhibit excessive breakout force, friction...

14 CFR 29.151 - Flight controls.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Flight controls. 29.151 Section 29.151... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Flight Flight Characteristics § 29.151 Flight controls. (a) Longitudinal, lateral, directional, and collective controls may not exhibit excessive breakout force, friction...

Capital Flight from Russia

OpenAIRE

Prakash Loungani; Paolo Mauro

2000-01-01

This paper documents the scale of capital flight from Russia, compares it with that observed in other countries, and reviews policy options. The evidence from other countries suggests that capital flight can be reversed once reforms take hold. The paper argues that capital flight from Russia can only be curbed through a medium-term reform strategy aimed at improving governance and macroeconomic performance, and strengthening the banking system. Capital controls result in costly distortions an...

Passengers waste production during flights.

Science.gov (United States)

Tofalli, Niki; Loizia, Pantelitsa; Zorpas, Antonis A

2017-12-20

We assume that during flights the amount of waste that is produced is limited. However, daily, approximately 8000 commercial airplanes fly above Europe's airspace while at the same time, more than 17,000 commercial flights exist in the entire world. Using primary data from airlines, which use the Larnaca's International Airport (LIA) in Cyprus, we have tried to understand why wastes are produced during a typical flight such as food waste, paper, and plastics, as well as how passengers affect the production of those wastes. The compositional analysis took place on 27 flights of 4 different airlines which used LIA as final destination. The evaluation indicated that the passenger's habits and ethics, and the policy of each airline produced different kinds of waste during the flights and especially food waste (FW). Furthermore, it was observed that the only waste management strategy that exists in place in the airport is the collection and the transportation of all those wastes from aircrafts and from the airport in the central unit for further treatment. Hence, this research indicated extremely difficulties to implement any specific waste minimization, or prevention practice or other sorting methods during the flights due to the limited time of the most flights (less than 3 h), the limited available space within the aircrafts, and the strictly safety roles that exist during the flights.

Path integral for relativistic particle theory

International Nuclear Information System (INIS)

Fradkin, E.S.; Gitman, D.M.; Shvartsman, Sh.M.

1990-06-01

An action for a relativistic spinning particle interacting with external electromagnetic field is considered in reparametrization and local supergauge invariant form. It is shown that various path integral representations derived for the causal Green function correspond to the different forms of the relativistic particle action. The analogy of the path integral derived with the Lagrangian path integral of the field theory is discussed. It is shown that to obtain the causal propagator, the integration over the null mode of the Lagrangian multiplier corresponding to the reparametrization invariance, has to be performed in the (0,+infinity) limits. (author). 23 refs

Supersymmetric gyratons in five dimensions

Energy Technology Data Exchange (ETDEWEB)

Caldarelli, Marco M [Dipartimento di Fisica dell' Universita di Milano Via Celoria 16, I-20133 Milan (Italy); Klemm, Dietmar [Dipartimento di Fisica dell' Universita di Milano Via Celoria 16, I-20133 Milan (Italy); Zorzan, Emanuele [Dipartimento di Fisica dell' Universita di Milano Via Celoria 16, I-20133 Milan (Italy)

2007-03-07

We obtain the gravitational and electromagnetic field of a spinning radiation beam-pulse (a gyraton) in minimal five-dimensional gauged supergravity and show under which conditions the solution preserves part of the supersymmetry. The configurations represent generalizations of Lobatchevski waves on AdS with nonzero angular momentum, and possess a Siklos-Virasoro reparametrization invariance. We compute the holographic stress-energy tensor of the solutions and show that it transforms without anomaly under these reparametrizations. Furthermore, we present supersymmetric gyratons both in gauged and ungauged five-dimensional supergravity coupled to an arbitrary number of vector supermultiplets, which include gyratons on domain walls.

A Flight Control System Architecture for the NASA AirSTAR Flight Test Infrastructure

Science.gov (United States)

Murch, Austin M.

2008-01-01

A flight control system architecture for the NASA AirSTAR infrastructure has been designed to address the challenges associated with safe and efficient flight testing of research control laws in adverse flight conditions. The AirSTAR flight control system provides a flexible framework that enables NASA Aviation Safety Program research objectives, and includes the ability to rapidly integrate and test research control laws, emulate component or sensor failures, inject automated control surface perturbations, and provide a baseline control law for comparison to research control laws and to increase operational efficiency. The current baseline control law uses an angle of attack command augmentation system for the pitch axis and simple stability augmentation for the roll and yaw axes.

Free Flight Rotorcraft Flight Test Vehicle Technology Development

Science.gov (United States)

Hodges, W. Todd; Walker, Gregory W.

1994-01-01

A rotary wing, unmanned air vehicle (UAV) is being developed as a research tool at the NASA Langley Research Center by the U.S. Army and NASA. This development program is intended to provide the rotorcraft research community an intermediate step between rotorcraft wind tunnel testing and full scale manned flight testing. The technologies under development for this vehicle are: adaptive electronic flight control systems incorporating artificial intelligence (AI) techniques, small-light weight sophisticated sensors, advanced telepresence-telerobotics systems and rotary wing UAV operational procedures. This paper briefly describes the system's requirements and the techniques used to integrate the various technologies to meet these requirements. The paper also discusses the status of the development effort. In addition to the original aeromechanics research mission, the technology development effort has generated a great deal of interest in the UAV community for related spin-off applications, as briefly described at the end of the paper. In some cases the technologies under development in the free flight program are critical to the ability to perform some applications.

76 FR 16236 - Prohibition Against Certain Flights Within the Tripoli (HLLL) Flight Information Region (FIR)

Science.gov (United States)

2011-03-23

... Tripoli (HLLL) Flight Information Region (FIR) AGENCY: Federal Aviation Administration (FAA), Department... the Tripoli (HLLL) Flight Information Region (FIR) by all U.S. air carriers; U.S. commercial operators...) Flight Information Region (FIR). (a) Applicability. This section applies to the following persons: (1...

78 FR 66261 - Certified Flight Instructor Flight Reviews; Recent Pilot in Command Experience; Airmen Online...

Science.gov (United States)

2013-11-05

...-0780; Amdt. No. 61-131] RIN 2120-AK23 Certified Flight Instructor Flight Reviews; Recent Pilot in Command Experience; Airmen Online Services; Confirmation of Effective Date AGENCY: Federal Aviation...-calendar month flight review requirements. This rule also clarifies that the generally applicable recent...

78 FR 56822 - Certified Flight Instructor Flight Reviews; Recent Pilot in Command Experience; Airmen Online...

Science.gov (United States)

2013-09-16

...-0780; Amdt. No. 61-131] RIN 2120-AK23 Certified Flight Instructor Flight Reviews; Recent Pilot in Command Experience; Airmen Online Services AGENCY: Federal Aviation Administration (FAA), DOT. ACTION... review requirements. This rule also clarifies that the generally applicable recent flight experience...

Flight to Safety from European Stock Markets

DEFF Research Database (Denmark)

Aslanidis, Nektarios; Christiansen, Charlotte

-return trade-off is positive and during flight-to-safety episodes it is negative. The effects of flight-to-safety episodes on the risk-return trade-off are qualitatively similar for own country flight-to-safety episodes, for flight from own country stock market to the US bond market, and for US flight......This paper investigates flight-to-safety from stocks to bonds in seven European markets. We use quantile regressions to identify flight-to-safety episodes. The simple risk-return trade-off on the stock markets is negative which is caused by flight-to-safety episodes: During normal periods, the risk...

Asset Analysis and Operational Concepts for Separation Assurance Flight Testing at Dryden Flight Research Center

Science.gov (United States)

Costa, Guillermo J.; Arteaga, Ricardo A.

2011-01-01

A preliminary survey of existing separation assurance and collision avoidance advancements, technologies, and efforts has been conducted in order to develop a concept of operations for flight testing autonomous separation assurance at Dryden Flight Research Center. This effort was part of the Unmanned Aerial Systems in the National Airspace System project. The survey focused primarily on separation assurance projects validated through flight testing (including lessons learned), however current forays into the field were also examined. Comparisons between current Dryden flight and range assets were conducted using House of Quality matrices in order to allow project management to make determinations regarding asset utilization for future flight tests. This was conducted in order to establish a body of knowledge of the current collision avoidance landscape, and thus focus Dryden s efforts more effectively towards the providing of assets and test ranges for future flight testing within this research field.

Solar array flight dynamic experiment

Science.gov (United States)

Schock, Richard W.

1987-01-01

The purpose of the Solar Array Flight Dynamic Experiment (SAFDE) is to demonstrate the feasibility of on-orbit measurement and ground processing of large space structures' dynamic characteristics. Test definition or verification provides the dynamic characteristic accuracy required for control systems use. An illumination/measurement system was developed to fly on space shuttle flight STS-41D. The system was designed to dynamically evaluate a large solar array called the Solar Array Flight Experiment (SAFE) that had been scheduled for this flight. The SAFDE system consisted of a set of laser diode illuminators, retroreflective targets, an intelligent star tracker receiver and the associated equipment to power, condition, and record the results. In six tests on STS-41D, data was successfully acquired from 18 retroreflector targets and ground processed, post flight, to define the solar array's dynamic characteristic. The flight experiment proved the viability of on-orbit test definition of large space structures dynamic characteristics. Future large space structures controllability should be greatly enhanced by this capability.

System Identification of Flight Mechanical Characteristics

OpenAIRE

Larsson, Roger

2013-01-01

With the demand for more advanced fighter aircraft, relying on relaxed stability or even unstable flight mechanical characteristics to gain flight performance, more focus has been put on model-based system engineering to help with the design work. The flight control system design is one important part that relies on this modeling. Therefore it has become more important to develop flight mechanical models that are highly accurate in the whole flight envelop. For today’s newly developed fighter...

Aerodynamics of bird flight

Directory of Open Access Journals (Sweden)

Dvořák Rudolf

2016-01-01

Full Text Available Unlike airplanes birds must have either flapping or oscillating wings (the hummingbird. Only such wings can produce both lift and thrust – two sine qua non attributes of flying.The bird wings have several possibilities how to obtain the same functions as airplane wings. All are realized by the system of flight feathers. Birds have also the capabilities of adjusting the shape of the wing according to what the immediate flight situation demands, as well as of responding almost immediately to conditions the flow environment dictates, such as wind gusts, object avoidance, target tracking, etc. In bird aerodynamics also the tail plays an important role. To fly, wings impart downward momentum to the surrounding air and obtain lift by reaction. How this is achieved under various flight situations (cruise flight, hovering, landing, etc., and what the role is of the wing-generated vortices in producing lift and thrust is discussed.The issue of studying bird flight experimentally from in vivo or in vitro experiments is also briefly discussed.

Production Support Flight Control Computers: Research Capability for F/A-18 Aircraft at Dryden Flight Research Center

Science.gov (United States)

Carter, John F.

1997-01-01

NASA Dryden Flight Research Center (DFRC) is working with the United States Navy to complete ground testing and initiate flight testing of a modified set of F/A-18 flight control computers. The Production Support Flight Control Computers (PSFCC) can give any fleet F/A-18 airplane an in-flight, pilot-selectable research control law capability. NASA DFRC can efficiently flight test the PSFCC for the following four reasons: (1) Six F/A-18 chase aircraft are available which could be used with the PSFCC; (2) An F/A-18 processor-in-the-loop simulation exists for validation testing; (3) The expertise has been developed in programming the research processor in the PSFCC; and (4) A well-defined process has been established for clearing flight control research projects for flight. This report presents a functional description of the PSFCC. Descriptions of the NASA DFRC facilities, PSFCC verification and validation process, and planned PSFCC projects are also provided.

Orion Exploration Flight Test Reaction Control System Jet Interaction Heating Environment from Flight Data

Science.gov (United States)

White, Molly E.; Hyatt, Andrew J.

2016-01-01

The Orion Multi-Purpose Crew Vehicle (MPCV) Reaction Control System (RCS) is critical to guide the vehicle along the desired trajectory during re-­-entry. However, this system has a significant impact on the convective heating environment to the spacecraft. Heating augmentation from the jet interaction (JI) drives thermal protection system (TPS) material selection and thickness requirements for the spacecraft. This paper describes the heating environment from the RCS on the afterbody of the Orion MPCV during Orion's first flight test, Exploration Flight Test 1 (EFT-1). These jet plumes interact with the wake of the crew capsule and cause an increase in the convective heating environment. Not only is there widespread influence from the jet banks, there may also be very localized effects. The firing history during EFT-1 will be summarized to assess which jet bank interaction was measured during flight. Heating augmentation factors derived from the reconstructed flight data will be presented. Furthermore, flight instrumentation across the afterbody provides the highest spatial resolution of the region of influence of the individual jet banks of any spacecraft yet flown. This distribution of heating augmentation across the afterbody will be derived from the flight data. Additionally, trends with possible correlating parameters will be investigated to assist future designs and ground testing programs. Finally, the challenges of measuring JI, applying this data to future flights and lessons learned will be discussed.

Flight testing a propulsion-controlled aircraft emergency flight control system on an F-15 airplane

Science.gov (United States)

Burcham, F. W., Jr.; Burken, John; Maine, Trindel A.

1994-01-01

Flight tests of a propulsion-controlled aircraft (PCA) system on an F-15 airplane have been conducted at the NASA Dryden Flight Research Center. The airplane was flown with all flight control surfaces locked both in the manual throttles-only mode and in an augmented system mode. In the latter mode, pilot thumbwheel commands and aircraft feedback parameters were used to position the throttles. Flight evaluation results showed that the PCA system can be used to land an airplane that has suffered a major flight control system failure safely. The PCA system was used to recover the F-15 airplane from a severe upset condition, descend, and land. Pilots from NASA, U.S. Air Force, U.S. Navy, and McDonnell Douglas Aerospace evaluated the PCA system and were favorably impressed with its capability. Manual throttles-only approaches were unsuccessful. This paper describes the PCA system operation and testing. It also presents flight test results and pilot comments.

Investigation of controlled flight into terrain : descriptions of flight paths for selected controlled flight into terrain (CFIT) aircraft accidents, 1985-1997

Science.gov (United States)

1999-03-01

This report documents an investigation of the flight paths of 13 selected controlled flight into terrain (CFIT) aircraft accidents that occurred between 1985 and 1997. The Operations Assessment Division (DTS-43) and the Aviation Safety Division (DTS-...

A random walk description of individual animal movement accounting for periods of rest

Science.gov (United States)

Tilles, Paulo F. C.; Petrovskii, Sergei V.; Natti, Paulo L.

2016-11-01

Animals do not move all the time but alternate the period of actual movement (foraging) with periods of rest (e.g. eating or sleeping). Although the existence of rest times is widely acknowledged in the literature and has even become a focus of increased attention recently, the theoretical approaches to describe animal movement by calculating the dispersal kernel and/or the mean squared displacement (MSD) rarely take rests into account. In this study, we aim to bridge this gap. We consider a composite stochastic process where the periods of active dispersal or `bouts' (described by a certain baseline probability density function (pdf) of animal dispersal) alternate with periods of immobility. For this process, we derive a general equation that determines the pdf of this composite movement. The equation is analysed in detail in two special but important cases such as the standard Brownian motion described by a Gaussian kernel and the Levy flight described by a Cauchy distribution. For the Brownian motion, we show that in the large-time asymptotics the effect of rests results in a rescaling of the diffusion coefficient. The movement occurs as a subdiffusive transition between the two diffusive asymptotics. Interestingly, the Levy flight case shows similar properties, which indicates a certain universality of our findings.

The development of a Flight Test Engineer's Workstation for the Automated Flight Test Management System

Science.gov (United States)

Tartt, David M.; Hewett, Marle D.; Duke, Eugene L.; Cooper, James A.; Brumbaugh, Randal W.

1989-01-01

The Automated Flight Test Management System (ATMS) is being developed as part of the NASA Aircraft Automation Program. This program focuses on the application of interdisciplinary state-of-the-art technology in artificial intelligence, control theory, and systems methodology to problems of operating and flight testing high-performance aircraft. The development of a Flight Test Engineer's Workstation (FTEWS) is presented, with a detailed description of the system, technical details, and future planned developments. The goal of the FTEWS is to provide flight test engineers and project officers with an automated computer environment for planning, scheduling, and performing flight test programs. The FTEWS system is an outgrowth of the development of ATMS and is an implementation of a component of ATMS on SUN workstations.

14 CFR 141.41 - Flight simulators, flight training devices, and training aids.

Science.gov (United States)

2010-01-01

..., and training aids. 141.41 Section 141.41 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION... aids. An applicant for a pilot school certificate or a provisional pilot school certificate must show that its flight simulators, flight training devices, training aids, and equipment meet the following...

The use of an automated flight test management system in the development of a rapid-prototyping flight research facility

Science.gov (United States)

Duke, Eugene L.; Hewett, Marle D.; Brumbaugh, Randal W.; Tartt, David M.; Antoniewicz, Robert F.; Agarwal, Arvind K.

1988-01-01

An automated flight test management system (ATMS) and its use to develop a rapid-prototyping flight research facility for artificial intelligence (AI) based flight systems concepts are described. The ATMS provides a flight test engineer with a set of tools that assist in flight planning and simulation. This system will be capable of controlling an aircraft during the flight test by performing closed-loop guidance functions, range management, and maneuver-quality monitoring. The rapid-prototyping flight research facility is being developed at the Dryden Flight Research Facility of the NASA Ames Research Center (Ames-Dryden) to provide early flight assessment of emerging AI technology. The facility is being developed as one element of the aircraft automation program which focuses on the qualification and validation of embedded real-time AI-based systems.

X-1A in flight with flight data superimposed

Science.gov (United States)

1953-01-01

This photo of the X-1A includes graphs of the flight data from Maj. Charles E. Yeager's Mach 2.44 flight on December 12, 1953. (This was only a few days short of the 50th anniversary of the Wright brothers' first powered flight.) After reaching Mach 2.44, then the highest speed ever reached by a piloted aircraft, the X-1A tumbled completely out of control. The motions were so violent that Yeager cracked the plastic canopy with his helmet. He finally recovered from a inverted spin and landed on Rogers Dry Lakebed. Among the data shown are Mach number and altitude (the two top graphs). The speed and altitude changes due to the tumble are visible as jagged lines. The third graph from the bottom shows the G-forces on the airplane. During the tumble, these twice reached 8 Gs or 8 times the normal pull of gravity at sea level. (At these G forces, a 200-pound human would, in effect, weigh 1,600 pounds if a scale were placed under him in the direction of the force vector.) Producing these graphs was a slow, difficult process. The raw data from on-board instrumentation recorded on oscillograph film. Human computers then reduced the data and recorded it on data sheets, correcting for such factors as temperature and instrument errors. They used adding machines or slide rules for their calculations, pocket calculators being 20 years in the future. Three second generation Bell Aircraft Corporations X-1s were built, though four were requested. They were the X-1A (48-1384); X-1B (48-1385); X-1C (canceled and never built); X-1D (48-1386). These aircraft were similar to the X-1s, except they were five feet longer, had conventional canopies, and were powered by Reaction Motors, Inc. XLR11-RM-5 rocket engines. The RM-5, like the previous engines, had no throttle and was controlled by igniting one or more of the four thrust chambers at will. The original program outline called for the X-1A and X-1B to be used for dynamic stability and air loads investigations. The X-1D was to be used

14 CFR 63.43 - Flight engineer courses.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Flight engineer courses. 63.43 Section 63...) AIRMEN CERTIFICATION: FLIGHT CREWMEMBERS OTHER THAN PILOTS Flight Engineers § 63.43 Flight engineer courses. An applicant for approval of a flight engineer course must submit a letter to the Administrator...

Design and utilization of a Flight Test Engineering Database Management System at the NASA Dryden Flight Research Facility

Science.gov (United States)

Knighton, Donna L.

1992-01-01

A Flight Test Engineering Database Management System (FTE DBMS) was designed and implemented at the NASA Dryden Flight Research Facility. The X-29 Forward Swept Wing Advanced Technology Demonstrator flight research program was chosen for the initial system development and implementation. The FTE DBMS greatly assisted in planning and 'mass production' card preparation for an accelerated X-29 research program. Improved Test Plan tracking and maneuver management for a high flight-rate program were proven, and flight rates of up to three flights per day, two times per week were maintained.

Magnesium and Space Flight

Science.gov (United States)

Smith, Scott M.; Zwart, Sara R.

2015-01-01

Magnesium is an essential nutrient for muscle, cardiovascular, and bone health on Earth, and during space flight. We sought to evaluate magnesium status in 43 astronauts (34 male, 9 female; 47 ± 5 years old, mean ± SD) before, during, and after 4–6-month space missions. We also studied individuals participating in a ground analog of space flight (head-down-tilt bed rest; n = 27 (17 male, 10 female), 35 ± 7 years old). We evaluated serum concentration and 24-h urinary excretion of magnesium, along with estimates of tissue magnesium status from sublingual cells. Serum magnesium increased late in flight, while urinary magnesium excretion was higher over the course of 180-day space missions. Urinary magnesium increased during flight but decreased significantly at landing. Neither serum nor urinary magnesium changed during bed rest. For flight and bed rest, significant correlations existed between the area under the curve of serum and urinary magnesium and the change in total body bone mineral content. Tissue magnesium concentration was unchanged after flight and bed rest. Increased excretion of magnesium is likely partially from bone and partially from diet, but importantly, it does not come at the expense of muscle tissue stores. While further study is needed to better understand the implications of these findings for longer space exploration missions, magnesium homeostasis and tissue status seem well maintained during 4–6-month space missions. PMID:26670248

Magnesium and Space Flight

Directory of Open Access Journals (Sweden)

Scott M. Smith

2015-12-01

Full Text Available Magnesium is an essential nutrient for muscle, cardiovascular, and bone health on Earth, and during space flight. We sought to evaluate magnesium status in 43 astronauts (34 male, 9 female; 47 ± 5 years old, mean ± SD before, during, and after 4–6-month space missions. We also studied individuals participating in a ground analog of space flight (head-down-tilt bed rest; n = 27 (17 male, 10 female, 35 ± 7 years old. We evaluated serum concentration and 24-h urinary excretion of magnesium, along with estimates of tissue magnesium status from sublingual cells. Serum magnesium increased late in flight, while urinary magnesium excretion was higher over the course of 180-day space missions. Urinary magnesium increased during flight but decreased significantly at landing. Neither serum nor urinary magnesium changed during bed rest. For flight and bed rest, significant correlations existed between the area under the curve of serum and urinary magnesium and the change in total body bone mineral content. Tissue magnesium concentration was unchanged after flight and bed rest. Increased excretion of magnesium is likely partially from bone and partially from diet, but importantly, it does not come at the expense of muscle tissue stores. While further study is needed to better understand the implications of these findings for longer space exploration missions, magnesium homeostasis and tissue status seem well maintained during 4–6-month space missions.

Flight Technical Error Analysis of the SATS Higher Volume Operations Simulation and Flight Experiments

Science.gov (United States)

Williams, Daniel M.; Consiglio, Maria C.; Murdoch, Jennifer L.; Adams, Catherine H.

2005-01-01

This paper provides an analysis of Flight Technical Error (FTE) from recent SATS experiments, called the Higher Volume Operations (HVO) Simulation and Flight experiments, which NASA conducted to determine pilot acceptability of the HVO concept for normal operating conditions. Reported are FTE results from simulation and flight experiment data indicating the SATS HVO concept is viable and acceptable to low-time instrument rated pilots when compared with today s system (baseline). Described is the comparative FTE analysis of lateral, vertical, and airspeed deviations from the baseline and SATS HVO experimental flight procedures. Based on FTE analysis, all evaluation subjects, low-time instrument-rated pilots, flew the HVO procedures safely and proficiently in comparison to today s system. In all cases, the results of the flight experiment validated the results of the simulation experiment and confirm the utility of the simulation platform for comparative Human in the Loop (HITL) studies of SATS HVO and Baseline operations.

Advanced in-flight measurement techniques

CERN Document Server

Lawson, Nicholas; Jentink, Henk; Kompenhans, Jürgen

2013-01-01

The book presents a synopsis of the main results achieved during the 3 year EU-project "Advanced Inflight Measurement Techniques (AIM)" which applied advanced image based measurement techniques to industrial flight testing. The book is intended to be not only an overview on the AIM activities but also a guide on the application of advanced optical measurement techniques for future flight testing. Furthermore it is a useful guide for engineers in the field of experimental methods and flight testing who face the challenge of a future requirement for the development of highly accurate non-intrusive in-flight measurement techniques.

Dynamic Models of Insurgent Activity

Science.gov (United States)

2014-05-19

one dimension that has recently been studied in the computer science community. The model involves movement with a speed proportional to a “fear...more realistic model of human locomotion. The movement of the criminal agents follows a biased Levy flight with step sizes distributed according to a...power-law distribution. The biased Brownian motion of the original model is then derived as a special case. Starting with an agent-based model, we

Analysis of Nondeterministic Search Patterns for Minimization of UAV Counter-Targeting

Science.gov (United States)

2013-03-01

64 Figure 4.9 Procerus Unicorn UAV [48] used in multi-UAV look-ahead Levy search demonstration conducted at 13-2 JIFX in February, 2013...minimum time or coverage path, minimal overlap, increased robustness to localization errors, etc. [3–5]. The role of randomized coverage and search...to the Procerus Unicorn UAV employed during these flight experiments, shown in Figure 4.9. Figure 4.10 shows the straight-line path between the major

Armstrong Flight Research Center Flight Test Capabilities and Opportunities for the Applications of Wireless Data Acquisition Systems

Science.gov (United States)

Hang, Richard

2015-01-01

The presentation will overview NASA Armstrong Flight Research Centers flight test capabilities, which can provide various means for flight testing of passive and active wireless sensor systems, also, it will address the needs of the wireless data acquisition solutions for the centers flight instrumentation issues such as additional weight caused by added instrumentation wire bundles, connectors, wire cables routing, moving components, etc., that the Passive Wireless Sensor Technology Workshop may help. The presentation shows the constraints and requirements that the wireless sensor systems will face in the flight test applications.

Flight demonstration of flight termination system and solid rocket motor ignition using semiconductor laser initiated ordnance

Science.gov (United States)

Schulze, Norman R.; Maxfield, B.; Boucher, C.

1995-01-01

Solid State Laser Initiated Ordnance (LIO) offers new technology having potential for enhanced safety, reduced costs, and improved operational efficiency. Concerns over the absence of programmatic applications of the technology, which has prevented acceptance by flight programs, should be abated since LIO has now been operationally implemented by the Laser Initiated Ordnance Sounding Rocket Demonstration (LOSRD) Program. The first launch of solid state laser diode LIO at the NASA Wallops Flight Facility (WFF) occurred on March 15, 1995 with all mission objectives accomplished. This project, Phase 3 of a series of three NASA Headquarters LIO demonstration initiatives, accomplished its objective by the flight of a dedicated, all-LIO sounding rocket mission using a two-stage Nike-Orion launch vehicle. LIO flight hardware, made by The Ensign-Bickford Company under NASA's first Cooperative Agreement with Profit Making Organizations, safely initiated three demanding pyrotechnic sequence events, namely, solid rocket motor ignition from the ground and in flight, and flight termination, i.e., as a Flight Termination System (FTS). A flight LIO system was designed, built, tested, and flown to support the objectives of quickly and inexpensively putting LIO through ground and flight operational paces. The hardware was fully qualified for this mission, including component testing as well as a full-scale system test. The launch accomplished all mission objectives in less than 11 months from proposal receipt. This paper concentrates on accomplishments of the ordnance aspects of the program and on the program's implementation and results. While this program does not generically qualify LIO for all applications, it demonstrated the safety, technical, and operational feasibility of those two most demanding applications, using an all solid state safe and arm system in critical flight applications.

Quantifying Pilot Contribution to Flight Safety During an In-Flight Airspeed Failure

Science.gov (United States)

Etherington, Timothy J.; Kramer, Lynda J.; Bailey, Randall E.; Kennedey, Kellie D.

2017-01-01

Accident statistics cite the flight crew as a causal factor in over 60% of large transport fatal accidents. Yet a well-trained and well-qualified crew is acknowledged as the critical center point of aircraft systems safety and an integral component of the entire commercial aviation system. A human-in-the-loop test was conducted using a Level D certified Boeing 737-800 simulator to evaluate the pilot's contribution to safety-of-flight during routine air carrier flight operations and in response to system failures. To quantify the human's contribution, crew complement was used as an independent variable in a between-subjects design. This paper details the crew's actions and responses while dealing with an in-flight airspeed failure. Accident statistics often cite flight crew error (Baker, 2001) as the primary contributor in accidents and incidents in transport category aircraft. However, the Air Line Pilots Association (2011) suggests "a well-trained and well-qualified pilot is acknowledged as the critical center point of the aircraft systems safety and an integral safety component of the entire commercial aviation system." This is generally acknowledged but cannot be verified because little or no quantitative data exists on how or how many accidents/incidents are averted by crew actions. Anecdotal evidence suggest crews handle failures on a daily basis and Aviation Safety Action Program data generally supports this assertion, even if the data is not released to the public. However without hard evidence, the contribution and means by which pilots achieve safety of flight is difficult to define. Thus, ways to improve the human ability to contribute or overcome deficiencies are ill-defined.

Theseus First Flight - May 24, 1996

Science.gov (United States)

1996-01-01

The Theseus prototype research aircraft shows off its high aspect-ratio wing as it lifts off from Rogers Dry Lake during its first test flight from NASA's Dryden Flight Research Center, Edwards, California, on May 24, 1996. The Theseus aircraft, built and operated by Aurora Flight Sciences Corporation, Manassas, Virginia, was a unique aircraft flown at NASA's Dryden Flight Research Center, Edwards, California, under a cooperative agreement between NASA and Aurora. Dryden hosted the Theseus program, providing hangar space and range safety for flight testing. Aurora Flight Sciences was responsible for the actual flight testing, vehicle flight safety, and operation of the aircraft. The Theseus remotely piloted aircraft flew its maiden flight on May 24, 1996, at Dryden. During its sixth flight on November 12, 1996, Theseus experienced an in-flight structural failure that resulted in the loss of the aircraft. As of the beginning of the year 2000, Aurora had not rebuilt the aircraft. Theseus was built for NASA under an innovative, $4.9 million fixed-price contract by Aurora Flight Sciences Corporation and its partners, West Virginia University, Morgantown, West Virginia, and Fairmont State College, Fairmont, West Virginia. The twin-engine, unpiloted vehicle had a 140-foot wingspan, and was constructed largely of composite materials. Powered by two 80-horsepower, turbocharged piston engines that drove twin 9-foot-diameter propellers, Theseus was designed to fly autonomously at high altitudes, with takeoff and landing under the active control of a ground-based pilot in a ground control station 'cockpit.' With the potential ability to carry 700 pounds of science instruments to altitudes above 60,000 feet for durations of greater than 24 hours, Theseus was intended to support research in areas such as stratospheric ozone depletion and the atmospheric effects of future high-speed civil transport aircraft engines. Instruments carried aboard Theseus also would be able to

Altitude exposures during commercial flight: a reappraisal.

Science.gov (United States)

Hampson, Neil B; Kregenow, David A; Mahoney, Anne M; Kirtland, Steven H; Horan, Kathleen L; Holm, James R; Gerbino, Anthony J

2013-01-01

Hypobaric hypoxia during commercial air travel has the potential to cause or worsen hypoxemia in individuals with pre-existing cardiopulmonary compromise. Knowledge of cabin altitude pressures aboard contemporary flights is essential to counseling patients accurately about flying safety. The objective of the study was to measure peak cabin altitudes during U.S. domestic commercial flights on a variety of aircraft. A handheld mountaineering altimeter was carried by the investigators in the plane cabin during commercial air travel and peak cabin altitude measured. The values were then compared between aircraft models, aircraft classes, and distances flown. The average peak cabin altitude on 207 flights aboard 17 different aircraft was 6341 +/- 1813 ft (1933 m +/- 553 m), significantly higher than when measured in a similar fashion in 1988. Peak cabin altitude was significantly higher for flights longer than 750 mi (7085 +/- 801 ft) compared to shorter flights (5160 +/- 2290 ft/1573 +/- 698 m). Cabin altitude increased linearly with flight distance for flights up to 750 mi in length, but was independent of flight distance for flights exceeding 750 mi. Peak cabin altitude was less than 5000 ft (1524 m) in 70% of flights shorter than 500 mi. Peak cabin altitudes greater than 8000 ft (2438 m) were measured on approximately 10% of the total flights. Peak cabin altitude on commercial aircraft flights has risen over time. Cabin altitude is lower with flights of shorter distance. Physicians should take these factors into account when determining an individual's need for supplemental oxygen during commercial air travel.

Poor flight performance in deep-diving cormorants.

Science.gov (United States)

Watanabe, Yuuki Y; Takahashi, Akinori; Sato, Katsufumi; Viviant, Morgane; Bost, Charles-André

2011-02-01

Aerial flight and breath-hold diving present conflicting morphological and physiological demands, and hence diving seabirds capable of flight are expected to face evolutionary trade-offs regarding locomotory performances. We tested whether Kerguelen shags Phalacrocorax verrucosus, which are remarkable divers, have poor flight capability using newly developed tags that recorded their flight air speed (the first direct measurement for wild birds) with propeller sensors, flight duration, GPS position and depth during foraging trips. Flight air speed (mean 12.7 m s(-1)) was close to the speed that minimizes power requirement, rather than energy expenditure per distance, when existing aerodynamic models were applied. Flights were short (mean 92 s), with a mean summed duration of only 24 min day(-1). Shags sometimes stayed at the sea surface without diving between flights, even on the way back to the colony, and surface durations increased with the preceding flight durations; these observations suggest that shags rested after flights. Our results indicate that their flight performance is physiologically limited, presumably compromised by their great diving capability (max. depth 94 m, duration 306 s) through their morphological adaptations for diving, including large body mass (enabling a large oxygen store), small flight muscles (to allow for large leg muscles for underwater propulsion) and short wings (to decrease air volume in the feathers and hence buoyancy). The compromise between flight and diving, as well as the local bathymetry, shape the three-dimensional foraging range (<26 km horizontally, <94 m vertically) in this bottom-feeding cormorant.

Development and Flight Test of an Augmented Thrust-Only Flight Control System on an MD-11 Transport Airplane

Science.gov (United States)

Burcham, Frank W., Jr.; Maine, Trindel A.; Burken, John J.; Pappas, Drew

1996-01-01

An emergency flight control system using only engine thrust, called Propulsion-Controlled Aircraft (PCA), has been developed and flight tested on an MD-11 airplane. In this thrust-only control system, pilot flight path and track commands and aircraft feedback parameters are used to control the throttles. The PCA system was installed on the MD-11 airplane using software modifications to existing computers. Flight test results show that the PCA system can be used to fly to an airport and safely land a transport airplane with an inoperative flight control system. In up-and-away operation, the PCA system served as an acceptable autopilot capable of extended flight over a range of speeds and altitudes. The PCA approaches, go-arounds, and three landings without the use of any non-nal flight controls have been demonstrated, including instrument landing system-coupled hands-off landings. The PCA operation was used to recover from an upset condition. In addition, PCA was tested at altitude with all three hydraulic systems turned off. This paper reviews the principles of throttles-only flight control; describes the MD-11 airplane and systems; and discusses PCA system development, operation, flight testing, and pilot comments.

Nutritional Biochemistry of Space Flight

Science.gov (United States)

Smith, Scott M.

2000-01-01

Adequate nutrition is critical for maintenance of crew health during and after extended-duration space flight. The impact of weightlessness on human physiology is profound, with effects on many systems related to nutrition, including bone, muscle, hematology, fluid and electrolyte regulation. Additionally, we have much to learn regarding the impact of weightlessness on absorption, mtabolism , and excretion of nutrients, and this will ultimately determine the nutrient requirements for extended-duration space flight. Existing nutritional requirements for extended-duration space flight have been formulated based on limited flight research, and extrapolation from ground-based research. NASA's Nutritional Biochemistry Laboratory is charged with defining the nutritional requirements for space flight. This is accomplished through both operational and research projects. A nutritional status assessment program is included operationally for all International Space Station astronauts. This medical requirement includes biochemical and dietary assessments, and is completed before, during, and after the missions. This program will provide information about crew health and nutritional status, and will also provide assessments of countermeasure efficacy. Ongoing research projects include studies of calcium and bone metabolism, and iron absorption and metabolism. The calcium studies include measurements of endocrine regulation of calcium homeostasis, biochemical marker of bone metabolism, and tracer kinetic studies of calcium movement in the body. These calcium kinetic studies allow for estimation of intestinal absorption, urinary excretion, and perhaps most importantly - deposition and resorption of calcium from bone. The Calcium Kinetics experiment is currently being prepared for flight on the Space Shuttle in 2001, and potentially for subsequent Shuttle and International Space Station missions. The iron study is intended to assess whether iron absorption is down-regulated dUl1ng

Effects of the regulating energy levy and energy tariffs on the cost effectiveness of energy efficient production of heat and cold

International Nuclear Information System (INIS)

2000-01-01

With respect to the title subject collective and stand-alone systems for house and office buildings were analyzed. For houses a high-efficiency boiler as reference system, and individual micro-cogeneration unit, an individual electric heat pump with a collective aquifer as heat source, an individual gas heat pump with outside air as a heat source, a collective cogeneration system, and a collective energy plant with cogeneration and an electric heat pump. For office buildings a high-efficiency boiler and a cooling machine as a reference system, an individual electric heat pump with an individual aquifer as a heat source, cold storage, collective cogeneration, and a collective energy plant with cogeneration and an electric heat pump. Also an overview is given of the changes that are taking place in the tariffs for natural gas, e.g. the use of so-called Commodity Services. Finally, the impact on prices of natural gas and electricity of the fact that the tax-free threshold of the regulating energy levy (REB, abbreviated in Dutch) will disappear is investigated. 5 refs

In-flight Fault Detection and Isolation in Aircraft Flight Control Systems

Science.gov (United States)

Azam, Mohammad; Pattipati, Krishna; Allanach, Jeffrey; Poll, Scott; Patterson-Hine, Ann

2005-01-01

In this paper we consider the problem of test design for real-time fault detection and isolation (FDI) in the flight control system of fixed-wing aircraft. We focus on the faults that are manifested in the control surface elements (e.g., aileron, elevator, rudder and stabilizer) of an aircraft. For demonstration purposes, we restrict our focus on the faults belonging to nine basic fault classes. The diagnostic tests are performed on the features extracted from fifty monitored system parameters. The proposed tests are able to uniquely isolate each of the faults at almost all severity levels. A neural network-based flight control simulator, FLTZ(Registered TradeMark), is used for the simulation of various faults in fixed-wing aircraft flight control systems for the purpose of FDI.

Digital virtual flight testing and evaluation method for flight characteristics airworthiness compliance of civil aircraft based on HQRM

Directory of Open Access Journals (Sweden)

Fan Liu

2015-02-01

Full Text Available In order to incorporate airworthiness requirements for flight characteristics into the entire development cycle of electronic flight control system (EFCS equipped civil aircraft, digital virtual flight testing and evaluation method based on handling qualities rating method (HQRM is proposed. First, according to HQRM, flight characteristics airworthiness requirements of civil aircraft in EFCS failure states are determined. On this basis, digital virtual flight testing model, comprising flight task digitized model, pilot controlling model, aircraft motion and atmospheric turbulence model, is used to simulate the realistic process of a pilot controlling an airplane to perform assigned flight tasks. According to the simulation results, flight characteristics airworthiness compliance of the airplane can be evaluated relying on the relevant regulations for handling qualities (HQ rating. Finally, this method is applied to a type of passenger airplane in a typical EFCS failure state, and preliminary conclusions concerning airworthiness compliance are derived quickly. The research results of this manuscript can provide important theoretical reference for EFCS design and actual airworthiness compliance verification of civil aircraft.

Supersonic Retropropulsion Flight Test Concepts

Science.gov (United States)

Post, Ethan A.; Dupzyk, Ian C.; Korzun, Ashley M.; Dyakonov, Artem A.; Tanimoto, Rebekah L.; Edquist, Karl T.

2011-01-01

NASA's Exploration Technology Development and Demonstration Program has proposed plans for a series of three sub-scale flight tests at Earth for supersonic retropropulsion, a candidate decelerator technology for future, high-mass Mars missions. The first flight test in this series is intended to be a proof-of-concept test, demonstrating successful initiation and operation of supersonic retropropulsion at conditions that replicate the relevant physics of the aerodynamic-propulsive interactions expected in flight. Five sub-scale flight test article concepts, each designed for launch on sounding rockets, have been developed in consideration of this proof-of-concept flight test. Commercial, off-the-shelf components are utilized as much as possible in each concept. The design merits of the concepts are compared along with their predicted performance for a baseline trajectory. The results of a packaging study and performance-based trade studies indicate that a sounding rocket is a viable launch platform for this proof-of-concept test of supersonic retropropulsion.

14 CFR 91.1061 - Augmented flight crews.

Science.gov (United States)

2010-01-01

...) Minimum After Duty Rest Period for Multi-Time Zone Flights 18 hours 24 hours ...) AIR TRAFFIC AND GENERAL OPERATING RULES GENERAL OPERATING AND FLIGHT RULES Fractional Ownership... crewmember, and no flight crewmember may accept an assignment, for flight time as a member of an augmented...

Getting started with Twitter Flight

CERN Document Server

Hamshere, Tom

2013-01-01

Getting Started with Twitter Flight is written with the intention to educate the readers, helping them learn how to build modular powerful applications with Flight, Twitter's cutting-edge JavaScript framework.This book is for anyone with a foundation in JavaScript who wants to build web applications. Flight is quick and easy to learn, built on technologies you already understand such as the DOM, events, and jQuery.

Flight telerobotic servicer legacy

Science.gov (United States)

Shattuck, Paul L.; Lowrie, James W.

1992-11-01

The Flight Telerobotic Servicer (FTS) was developed to enhance and provide a safe alternative to human presence in space. The first step for this system was a precursor development test flight (DTF-1) on the Space Shuttle. DTF-1 was to be a pathfinder for manned flight safety of robotic systems. The broad objectives of this mission were three-fold: flight validation of telerobotic manipulator (design, control algorithms, man/machine interfaces, safety); demonstration of dexterous manipulator capabilities on specific building block tasks; and correlation of manipulator performance in space with ground predictions. The DTF-1 system is comprised of a payload bay element (7-DOF manipulator with controllers, end-of-arm gripper and camera, telerobot body with head cameras and electronics module, task panel, and MPESS truss) and an aft flight deck element (force-reflecting hand controller, crew restraint, command and display panel and monitors). The approach used to develop the DTF-1 hardware, software and operations involved flight qualification of components from commercial, military, space, and R controller, end-of-arm tooling, force/torque transducer) and the development of the telerobotic system for space applications. The system is capable of teleoperation and autonomous control (advances state of the art); reliable (two-fault tolerance); and safe (man-rated). Benefits from the development flight included space validation of critical telerobotic technologies and resolution of significant safety issues relating to telerobotic operations in the Shuttle bay or in the vicinity of other space assets. This paper discusses the lessons learned and technology evolution that stemmed from developing and integrating a dexterous robot into a manned system, the Space Shuttle. Particular emphasis is placed on the safety and reliability requirements for a man-rated system as these are the critical factors which drive the overall system architecture. Other topics focused on include

Microgravity Flight - Accommodating Non-Human Primates

Science.gov (United States)

Dalton, Bonnie P.; Searby, Nancy; Ostrach, Louis

1994-01-01

Spacelab Life Sciences-3 (SLS-3) was scheduled to be the first United States man-tended microgravity flight containing Rhesus monkeys. The goal of this flight as in the five untended Russian COSMOS Bion flights and an earlier American Biosatellite flight, was to understand the biomedical and biological effects of a microgravity environment using the non-human primate as human surrogate. The SLS-3/Rhesus Project and COSMOS Primate-BIOS flights all utilized the rhesus monkey, Macaca mulatta. The ultimate objective of all flights with an animal surrogate has been to evaluate and understand biological mechanisms at both the system and cellular level, thus enabling rational effective countermeasures for future long duration human activity under microgravity conditions and enabling technical application to correction of common human physiological problems within earth's gravity, e.g., muscle strength and reloading, osteoporosis, immune deficiency diseases. Hardware developed for the SLS-3/Rhesus Project was the result of a joint effort with the French Centre National d'Etudes Spatiales (CNES) and the United States National Aeronautics and Space Administration (NASA) extending over the last decade. The flight hardware design and development required implementation of sufficient automation to insure flight crew and animal bio-isolation and maintenance with minimal impact to crew activities. A variety of hardware of varying functional capabilities was developed to support the scientific objectives of the original 22 combined French and American experiments, along with 5 Russian co-investigations, including musculoskeletal, metabolic, and behavioral studies. Unique elements of the Rhesus Research Facility (RRF) included separation of waste for daily delivery of urine and fecal samples for metabolic studies and a psychomotor test system for behavioral studies along with monitored food measurement. As in untended flights, telemetry measurements would allow monitoring of

Low Density Supersonic Decelerator Flight Dynamics Test-1 Flight Design and Targeting

Science.gov (United States)

Ivanov, Mark

2015-01-01

NASA's Low Density Supersonic Decelerator (LDSD) program was established to identify, develop, and eventually qualify to Test [i.e. Technology] Readiness Level (TRL) - 6 aerodynamic decelerators for eventual use on Mars. Through comprehensive Mars application studies, two distinct Supersonic Inflatable Aerodynamic Decelerator (SIAD) designs were chosen that afforded the optimum balance of benefit, cost, and development risk. In addition, a Supersonic Disk Sail (SSDS) parachute design was chosen that satisfied the same criteria. The final phase of the multi-tiered qualification process involves Earth Supersonic Flight Dynamics Tests (SFDTs) within environmental conditions similar to those that would be experienced during a Mars Entry, Descent, and Landing (EDL) mission. The first of these flight tests (i.e. SFDT-1) was completed on June 28, 2014 with two more tests scheduled for the summer of 2015 and 2016, respectively. The basic flight design for all the SFDT flights is for the SFDT test vehicle to be ferried to a float altitude of 120 kilo-feet by a 34 thousand cubic feet (Mcf) heavy lift helium balloon. Once float altitude is reached, the test vehicle is released from the balloon, spun-up for stability, and accelerated to supersonic speeds using a Star48 solid rocket motor. After burnout of the Star48 motor the vehicle decelerates to pre-flight selected test conditions for the deployment of the SIAD system. After further deceleration with the SIAD deployed, the SSDS parachute is then deployed stressing the performance of the parachute in the wake of the SIAD augmented blunt body. The test vehicle/SIAD/parachute system then descends to splashdown in the Pacific Ocean for eventual recovery. This paper will discuss the development of both the test vehicle and the trajectory sequence including design trade-offs resulting from the interaction of both engineering efforts. In addition, the SFDT-1 nominal trajectory design and associated sensitivities will be discussed

Aging Enhances Indirect Flight Muscle Fiber Performance yet Decreases Flight Ability in Drosophila

Energy Technology Data Exchange (ETDEWEB)

Miller, Mark S.; Lekkas, Panagiotis; Braddock, Joan M.; Farman, Gerrie P.; Ballif, Bryan A.; Irving, Thomas C.; Maughan, David W.; Vigoreaux, Jim O. (IIT); (Vermont)

2008-10-02

We investigated the effects of aging on Drosophila melanogaster indirect flight muscle from the whole organism to the actomyosin cross-bridge. Median-aged (49-day-old) flies were flight impaired, had normal myofilament number and packing, barely longer sarcomeres, and slight mitochondrial deterioration compared with young (3-day-old) flies. Old (56-day-old) flies were unable to beat their wings, had deteriorated ultrastructure with severe mitochondrial damage, and their skinned fibers failed to activate with calcium. Small-amplitude sinusoidal length perturbation analysis showed median-aged indirect flight muscle fibers developed greater than twice the isometric force and power output of young fibers, yet cross-bridge kinetics were similar. Large increases in elastic and viscous moduli amplitude under active, passive, and rigor conditions suggest that median-aged fibers become stiffer longitudinally. Small-angle x-ray diffraction indicates that myosin heads move increasingly toward the thin filament with age, accounting for the increased transverse stiffness via cross-bridge formation. We propose that the observed protein composition changes in the connecting filaments, which anchor the thick filaments to the Z-disk, produce compensatory increases in longitudinal stiffness, isometric tension, power and actomyosin interaction in aging indirect flight muscle. We also speculate that a lack of MgATP due to damaged mitochondria accounts for the decreased flight performance.

Ares I-X Flight Test Philosophy

Science.gov (United States)

Davis, S. R.; Tuma, M. L.; Heitzman, K.

2007-01-01

In response to the Vision for Space Exploration, the National Aeronautics and Space Administration (NASA) has defined a new space exploration architecture to return humans to the Moon and prepare for human exploration of Mars. One of the first new developments will be the Ares I Crew Launch Vehicle (CLV), which will carry the Orion Crew Exploration Vehicle (CEV), into Low Earth Orbit (LEO) to support International Space Station (ISS) missions and, later, support lunar missions. As part of Ares I development, NASA will perform a series of Ares I flight tests. The tests will provide data that will inform the engineering and design process and verify the flight hardware and software. The data gained from the flight tests will be used to certify the new Ares/Orion vehicle for human space flight. The primary objectives of this first flight test (Ares I-X) are the following: Demonstrate control of a dynamically similar integrated Ares CLV/Orion CEV using Ares CLV ascent control algorithms; Perform an in-flight separation/staging event between an Ares I-similar First Stage and a representative Upper Stage; Demonstrate assembly and recovery of a new Ares CLV-like First Stage element at Kennedy Space Center (KSC); Demonstrate First Stage separation sequencing, and quantify First Stage atmospheric entry dynamics and parachute performance; and Characterize the magnitude of the integrated vehicle roll torque throughout the First Stage (powered) flight. This paper will provide an overview of the Ares I-X flight test process and details of the individual flight tests.

Remote radio control of insect flight

Directory of Open Access Journals (Sweden)

Hirotaka Sato

2009-10-01

Full Text Available We demonstrated the remote control of insects in free flight via an implantable radio-equipped miniature neural stimulating system. The pronotum mounted system consisted of neural stimulators, muscular stimulators, a radio transceiver-equipped microcontroller and a microbattery. Flight initiation, cessation and elevation control were accomplished through neural stimulus of the brain which elicited, suppressed or modulated wing oscillation. Turns were triggered through the direct muscular stimulus of either of the basalar muscles. We characterized the response times, success rates, and free-flight trajectories elicited by our neural control systems in remotely-controlled beetles. We believe this type of technology will open the door to in-flight perturbation and recording of insect flight responses.

Remote radio control of insect flight.

Science.gov (United States)

Sato, Hirotaka; Berry, Christopher W; Peeri, Yoav; Baghoomian, Emen; Casey, Brendan E; Lavella, Gabriel; Vandenbrooks, John M; Harrison, Jon F; Maharbiz, Michel M

2009-01-01

We demonstrated the remote control of insects in free flight via an implantable radio-equipped miniature neural stimulating system. The pronotum mounted system consisted of neural stimulators, muscular stimulators, a radio transceiver-equipped microcontroller and a microbattery. Flight initiation, cessation and elevation control were accomplished through neural stimulus of the brain which elicited, suppressed or modulated wing oscillation. Turns were triggered through the direct muscular stimulus of either of the basalar muscles. We characterized the response times, success rates, and free-flight trajectories elicited by our neural control systems in remotely controlled beetles. We believe this type of technology will open the door to in-flight perturbation and recording of insect flight responses.

Flight Test Maneuvers for Efficient Aerodynamic Modeling

Science.gov (United States)

Morelli, Eugene A.

2011-01-01

Novel flight test maneuvers for efficient aerodynamic modeling were developed and demonstrated in flight. Orthogonal optimized multi-sine inputs were applied to aircraft control surfaces to excite aircraft dynamic response in all six degrees of freedom simultaneously while keeping the aircraft close to chosen reference flight conditions. Each maneuver was designed for a specific modeling task that cannot be adequately or efficiently accomplished using conventional flight test maneuvers. All of the new maneuvers were first described and explained, then demonstrated on a subscale jet transport aircraft in flight. Real-time and post-flight modeling results obtained using equation-error parameter estimation in the frequency domain were used to show the effectiveness and efficiency of the new maneuvers, as well as the quality of the aerodynamic models that can be identified from the resultant flight data.

Comparison of Commercial Aircraft Fuel Requirements in Regards to FAR, Flight Profile Simulation, and Flight Operational Techniques

Science.gov (United States)

Heitzman, Nicholas

There are significant fuel consumption consequences for non-optimal flight operations. This study is intended to analyze and highlight areas of interest that affect fuel consumption in typical flight operations. By gathering information from actual flight operators (pilots, dispatch, performance engineers, and air traffic controllers), real performance issues can be addressed and analyzed. A series of interviews were performed with various individuals in the industry and organizations. The wide range of insight directed this study to focus on FAA regulations, airline policy, the ATC system, weather, and flight planning. The goal is to highlight where operational performance differs from design intent in order to better connect optimization with actual flight operations. After further investigation and consensus from the experienced participants, the FAA regulations do not need any serious attention until newer technologies and capabilities are implemented. The ATC system is severely out of date and is one of the largest limiting factors in current flight operations. Although participants are pessimistic about its timely implementation, the FAA's NextGen program for a future National Airspace System should help improve the efficiency of flight operations. This includes situational awareness, weather monitoring, communication, information management, optimized routing, and cleaner flight profiles like Required Navigation Performance (RNP) and Continuous Descent Approach (CDA). Working off the interview results, trade-studies were performed using an in-house flight profile simulation of a Boeing 737-300, integrating NASA legacy codes EDET and NPSS with a custom written mission performance and point-performance "Skymap" calculator. From these trade-studies, it was found that certain flight conditions affect flight operations more than others. With weather, traffic, and unforeseeable risks, flight planning is still limited by its high level of precaution. From this

14 CFR 125.265 - Flight engineer requirements.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Flight engineer requirements. 125.265... Requirements § 125.265 Flight engineer requirements. (a) No person may operate an airplane for which a flight engineer is required by the type certification requirements without a flight crewmember holding a current...

Development and Flight Testing of a Neural Network Based Flight Control System on the NF-15B Aircraft

Science.gov (United States)

Bomben, Craig R.; Smolka, James W.; Bosworth, John T.; Silliams-Hayes, Peggy S.; Burken, John J.; Larson, Richard R.; Buschbacher, Mark J.; Maliska, Heather A.

2006-01-01

The Intelligent Flight Control System (IFCS) project at the NASA Dryden Flight Research Center, Edwards AFB, CA, has been investigating the use of neural network based adaptive control on a unique NF-15B test aircraft. The IFCS neural network is a software processor that stores measured aircraft response information to dynamically alter flight control gains. In 2006, the neural network was engaged and allowed to learn in real time to dynamically alter the aircraft handling qualities characteristics in the presence of actual aerodynamic failure conditions injected into the aircraft through the flight control system. The use of neural network and similar adaptive technologies in the design of highly fault and damage tolerant flight control systems shows promise in making future aircraft far more survivable than current technology allows. This paper will present the results of the IFCS flight test program conducted at the NASA Dryden Flight Research Center in 2006, with emphasis on challenges encountered and lessons learned.

14 CFR 63.42 - Flight engineer certificate issued on basis of a foreign flight engineer license.

Science.gov (United States)

2010-01-01

... section, may have a flight engineer certificate issued to him for the operation of civil aircraft of U.S... engineer certificate issued under this section may act as a flight engineer of a civil aircraft of U.S... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Flight engineer certificate issued on basis...

14 CFR 91.1095 - Initial and transition training and checking: Flight instructors (aircraft), flight instructors...

Science.gov (United States)

2010-01-01

... instructor certificate— (i) The fundamental principles of the teaching-learning process; (ii) Teaching... Management § 91.1095 Initial and transition training and checking: Flight instructors (aircraft), flight...

14 CFR 121.387 - Flight engineer.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Flight engineer. 121.387 Section 121.387..., FLAG, AND SUPPLEMENTAL OPERATIONS Airman and Crewmember Requirements § 121.387 Flight engineer. No... holding a current flight engineer certificate. For each airplane type certificated after January 1, 1964...

Nuptial flights behavior of the African weaver ant, Oecophylla longinoda Latreille (Hymenoptera: Formicidae) and weather factors triggering flights

DEFF Research Database (Denmark)

Nene, Wilson; Rwegasira, Gration; Nielsen, Mogens Gissel

2016-01-01

years, we found that sexuals aggregate on nest surfaces prior to flights. We also found that flights took place during the raining season, and all flights took place in evenings just before sunset. Further to these, days with flights were associated with higher relative humidity and less sun shine...... collection of mated queens to stock ant nurseries that supply ant colonies for IPM-programs....

An overview of integrated flight-propulsion controls flight research on the NASA F-15 research airplane

Science.gov (United States)

Burcham, Frank W., Jr.; Gatlin, Donald H.; Stewart, James F.

1995-01-01

The NASA Dryden Flight Research Center has been conducting integrated flight-propulsion control flight research using the NASA F-15 airplane for the past 12 years. The research began with the digital electronic engine control (DEEC) project, followed by the F100 Engine Model Derivative (EMD). HIDEC (Highly Integrated Digital Electronic Control) became the umbrella name for a series of experiments including: the Advanced Digital Engine Controls System (ADECS), a twin jet acoustics flight experiment, self-repairing flight control system (SRFCS), performance-seeking control (PSC), and propulsion controlled aircraft (PCA). The upcoming F-15 project is ACTIVE (Advanced Control Technology for Integrated Vehicles). This paper provides a brief summary of these activities and provides background for the PCA and PSC papers, and includes a bibliography of all papers and reports from the NASA F-15 project.

Theseus on Take-off for First Flight

Science.gov (United States)

1996-01-01

The Theseus prototype research aircraft takes off for its first test flight from NASA's Dryden Flight Research Center, Edwards, California, on May 24, 1996. The Theseus aircraft, built and operated by Aurora Flight Sciences Corporation, Manassas, Virginia, was a unique aircraft flown at NASA's Dryden Flight Research Center, Edwards, California, under a cooperative agreement between NASA and Aurora. Dryden hosted the Theseus program, providing hangar space and range safety for flight testing. Aurora Flight Sciences was responsible for the actual flight testing, vehicle flight safety, and operation of the aircraft. The Theseus remotely piloted aircraft flew its maiden flight on May 24, 1996, at Dryden. During its sixth flight on November 12, 1996, Theseus experienced an in-flight structural failure that resulted in the loss of the aircraft. As of the beginning of the year 2000, Aurora had not rebuilt the aircraft. Theseus was built for NASA under an innovative, $4.9 million fixed-price contract by Aurora Flight Sciences Corporation and its partners, West Virginia University, Morgantown, West Virginia, and Fairmont State College, Fairmont, West Virginia. The twin-engine, unpiloted vehicle had a 140-foot wingspan, and was constructed largely of composite materials. Powered by two 80-horsepower, turbocharged piston engines that drove twin 9-foot-diameter propellers, Theseus was designed to fly autonomously at high altitudes, with takeoff and landing under the active control of a ground-based pilot in a ground control station 'cockpit.' With the potential ability to carry 700 pounds of science instruments to altitudes above 60,000 feet for durations of greater than 24 hours, Theseus was intended to support research in areas such as stratospheric ozone depletion and the atmospheric effects of future high-speed civil transport aircraft engines. Instruments carried aboard Theseus also would be able to validate satellite-based global environmental change measurements. Dryden

A unified flight control methodology for a compound rotorcraft in fundamental and aerobatic maneuvering flight

Science.gov (United States)

Thorsen, Adam

This study investigates a novel approach to flight control for a compound rotorcraft in a variety of maneuvers ranging from fundamental to aerobatic in nature. Fundamental maneuvers are a class of maneuvers with design significance that are useful for testing and tuning flight control systems along with uncovering control law deficiencies. Aerobatic maneuvers are a class of aggressive and complex maneuvers with more operational significance. The process culminating in a unified approach to flight control includes various control allocation studies for redundant controls in trim and maneuvering flight, an efficient methodology to simulate non-piloted maneuvers with varying degrees of complexity, and the setup of an unconventional control inceptor configuration along with the use of a flight simulator to gather pilot feedback in order to improve the unified control architecture. A flight path generation algorithm was developed to calculate control inceptor commands required for a rotorcraft in aerobatic maneuvers. This generalized algorithm was tailored to generate flight paths through optimization methods in order to satisfy target terminal position coordinates or to minimize the total time of a particular maneuver. Six aerobatic maneuvers were developed drawing inspiration from air combat maneuvers of fighter jet aircraft: Pitch-Back Turn (PBT), Combat Ascent Turn (CAT), Combat Descent Turn (CDT), Weaving Pull-up (WPU), Combat Break Turn (CBT), and Zoom and Boom (ZAB). These aerobatic maneuvers were simulated at moderate to high advance ratios while fundamental maneuvers of the compound including level accelerations/decelerations, climbs, descents, and turns were investigated across the entire flight envelope to evaluate controller performance. The unified control system was developed to allow controls to seamlessly transition between manual and automatic allocations while ensuring that the axis of control for a particular inceptor remained constant with flight

14 CFR 415.115 - Flight safety.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Flight safety. 415.115 Section 415.115... TRANSPORTATION LICENSING LAUNCH LICENSE Safety Review and Approval for Launch of an Expendable Launch Vehicle From a Non-Federal Launch Site § 415.115 Flight safety. (a) Flight safety analysis. An applicant's...

Retrieving Balloon Data in Flight

Data.gov (United States)

National Aeronautics and Space Administration — NASA's Ultra Long Duration Balloon (ULDB) program will soon make flights lasting up to 100 days. Some flights may generate high data rates and retrieving this data...

14 CFR 417.107 - Flight safety.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Flight safety. 417.107 Section 417.107... TRANSPORTATION LICENSING LAUNCH SAFETY Launch Safety Responsibilities § 417.107 Flight safety. (a) Flight safety... safety system that satisfies subpart D of this part as follows, unless § 417.125 applies. (1) In the...

Mini-Sniffer II in Flight

Science.gov (United States)

1976-01-01

This photograph shows the second Mini-Sniffer undergoing flight testing over Rogers Dry Lake in Edwards, California. This version of the Mini-Sniffer lacked the canard of the original version and had wing tips and tail booms added. The Mini-Sniffer was a remotely controlled, propeller-driven vehicle developed at the NASA Flight Research Center (which became the Dryden Flight Research Center, Edwards, California, in 1976) as a potential platform to sample the upper atmosphere for pollution. The vehicle, flown from 1975 to 1977, was one of the earliest attempts by NASA to develop an aircraft that could sense turbulence and measure natural and human-produced atmospheric pollutants at altitudes above 80,000 feet with a variable-load propeller that was never flight-tested. Three Mini-Sniffer vehicles were built. The number 1 Mini-Sniffer vehicle had swept wings with a span of 18 feet and canards on the nose. It flew 12 flights with the gas-powered engine at low altitudes of around 2,500 feet. The number 1 vehicle was then modified into version number 2 by removing the canards and wing rudders and adding wing tips and tail booms. Twenty flights were made with this version, up to altitudes of 20,000 feet. The number 3 vehicle had a longer fuselage, was lighter in weight, and was powered by the non-air-breathing hydrazine engine designed by NASA's Johnson Space Center in Houston, Texas. This version was designed to fly a 25-pound payload to an altitude of 70,000 feet for one hour or to climb to 90,000 feet and glide back. The number 3 Mini-Sniffer made one flight to 20,000 feet and was not flown again because of a hydrazine leak problem. All three versions used a pusher propeller to free the nose area for an atmospheric-sampling payload. At various times the Mini-Sniffer has been considered for exploration in the carbon dioxide atmosphere of the planet Mars, where the gravity (38 percent of that on Earth) would reduce the horsepower needed for flight.

Young PHD's in Human Space Flight

Science.gov (United States)

Wilson, Eleanor

2002-01-01

The Cooperating Hampton Roads Organizations for Minorities in Engineering (CHROME) in cooperation with the NASA Office of Space Flight, Human Exploration and Development of Space Enterprise sponsored a summer institute, Young PHD#s (Persons Having Dreams) in Human Space Flight. This 3-day institute used the curriculum of a workshop designed for space professionals, 'Human Space Flight-Analysis and Design: An Integrated, Systematic Approach.' The content was tailored to a high school audience. This institute seeks to stimulate the interest of pre-college students in space flight and motivate them to pursue further experiences in this field. Additionally, this institute will serve as a pilot model for a pre- collegiate training program that can be replicated throughout the country. The institute was complemented with a trip to the Goddard Space Flight Center.

Lessons Learned and Flight Results from the F15 Intelligent Flight Control System Project

Science.gov (United States)

Bosworth, John

2006-01-01

A viewgraph presentation on the lessons learned and flight results from the F15 Intelligent Flight Control System (IFCS) project is shown. The topics include: 1) F-15 IFCS Project Goals; 2) Motivation; 3) IFCS Approach; 4) NASA F-15 #837 Aircraft Description; 5) Flight Envelope; 6) Limited Authority System; 7) NN Floating Limiter; 8) Flight Experiment; 9) Adaptation Goals; 10) Handling Qualities Performance Metric; 11) Project Phases; 12) Indirect Adaptive Control Architecture; 13) Indirect Adaptive Experience and Lessons Learned; 14) Gen II Direct Adaptive Control Architecture; 15) Current Status; 16) Effect of Canard Multiplier; 17) Simulated Canard Failure Stab Open Loop; 18) Canard Multiplier Effect Closed Loop Freq. Resp.; 19) Simulated Canard Failure Stab Open Loop with Adaptation; 20) Canard Multiplier Effect Closed Loop with Adaptation; 21) Gen 2 NN Wts from Simulation; 22) Direct Adaptive Experience and Lessons Learned; and 23) Conclusions

Pigeons (C. livia Follow Their Head during Turning Flight: Head Stabilization Underlies the Visual Control of Flight

Directory of Open Access Journals (Sweden)

Ivo G. Ros

2017-12-01

Full Text Available Similar flight control principles operate across insect and vertebrate fliers. These principles indicate that robust solutions have evolved to meet complex behavioral challenges. Following from studies of visual and cervical feedback control of flight in insects, we investigate the role of head stabilization in providing feedback cues for controlling turning flight in pigeons. Based on previous observations that the eyes of pigeons remain at relatively fixed orientations within the head during flight, we test potential sensory control inputs derived from head and body movements during 90° aerial turns. We observe that periods of angular head stabilization alternate with rapid head repositioning movements (head saccades, and confirm that control of head motion is decoupled from aerodynamic and inertial forces acting on the bird's continuously rotating body during turning flapping flight. Visual cues inferred from head saccades correlate with changes in flight trajectory; whereas the magnitude of neck bending predicts angular changes in body position. The control of head motion to stabilize a pigeon's gaze may therefore facilitate extraction of important motion cues, in addition to offering mechanisms for controlling body and wing movements. Strong similarities between the sensory flight control of birds and insects may also inspire novel designs of robust controllers for human-engineered autonomous aerial vehicles.

14 CFR 61.41 - Flight training received from flight instructors not certificated by the FAA.

Science.gov (United States)

2010-01-01

... the FAA. (a) A person may credit flight training toward the requirements of a pilot certificate or... flight instructor described in paragraph (a) of this section is only authorized to give endorsements to...

X-36 in Flight near Edge of Rogers Dry Lake during 5th Flight

Science.gov (United States)

1997-01-01

This photo shows the X-36 Tailless Fighter Agility Research Aircraft passing over the edge of Rogers Dry Lake as the remotely-piloted aircraft flies over Edwards Air Force Base on a June 1997 research flight. The NASA/Boeing X-36 Tailless Fighter Agility Research Aircraft program successfully demonstrated the tailless fighter design using advanced technologies to improve the maneuverability and survivability of possible future fighter aircraft. The program met or exceeded all project goals. For 31 flights during 1997 at the Dryden Flight Research Center, Edwards, California, the project team examined the aircraft's agility at low speed / high angles of attack and at high speed / low angles of attack. The aircraft's speed envelope reached up to 206 knots (234 mph). This aircraft was very stable and maneuverable. It handled very well. The X-36 vehicle was designed to fly without the traditional tail surfaces common on most aircraft. Instead, a canard forward of the wing was used as well as split ailerons and an advanced thrust-vectoring nozzle for directional control. The X-36 was unstable in both pitch and yaw axes, so an advanced, single-channel digital fly-by-wire control system (developed with some commercially available components) was put in place to stabilize the aircraft. Using a video camera mounted in the nose of the aircraft and an onboard microphone, the X-36 was remotely controlled by a pilot in a ground station virtual cockpit. A standard fighter-type head-up display (HUD) and a moving-map representation of the vehicle's position within the range in which it flew provided excellent situational awareness for the pilot. This pilot-in-the-loop approach eliminated the need for expensive and complex autonomous flight control systems and the risks associated with their inability to deal with unknown or unforeseen phenomena in flight. Fully fueled the X-36 prototype weighed approximately 1,250 pounds. It was 19 feet long and three feet high with a wingspan of

Sub-recoil cooling up to nano-Kelvin. Direct measurement of spatial coherency length. New tests for Levy statistics; Refroidissement laser subrecul au nanokelvin. Mesure directe de la longueur de coherence spatiale. Nouveaux tests des statistiques de Levy

Energy Technology Data Exchange (ETDEWEB)

Saubamea, B

1998-12-15

This thesis presents a new method to measure the temperature of ultracold atoms from the spatial autocorrelation function of the atomic wave-packets. We thus determine the temperature of metastable helium-4 atoms cooled by velocity selective dark resonance, a method known to cool the atoms below the temperature related to the emission or the absorption of a single photon by an atom at rest, namely the recoil temperature. This cooling mechanism prepares each atom in a coherent superposition of two wave-packets with opposite mean momenta, which are initially superimposed and then drift apart. By measuring the temporal decay of their overlap, we have access to the Fourier transform of the momentum distribution of the atoms. Using this method, we can measure temperatures as low as 5 nK, 800 times as small as the recoil temperature. Moreover we study in detail the exact shape of the momentum distribution and compare the experimental results with two different theoretical approaches: a quantum Monte Carlo simulation and an analytical model based on Levy statistics. We compare the calculated line shape with the one deduced from simulations, and each theoretical model with experimental data. A very good agreement is found with each approach. We thus demonstrate the validity of the statistical model of sub-recoil cooling and give the first experimental evidence of some of its characteristics: the absence of steady-state, the self-similarity and the non Lorentzian shape of the momentum distribution of the cooled atoms. All these aspects are related to the non ergodicity of sub-recoil cooling. (author)

Post-Flight Data Analysis Tool

Science.gov (United States)

George, Marina

2018-01-01

A software tool that facilitates the retrieval and analysis of post-flight data. This allows our team and other teams to effectively and efficiently analyze and evaluate post-flight data in order to certify commercial providers.

14 CFR 61.193 - Flight instructor privileges.

Science.gov (United States)

2010-01-01

... than Flight Instructors With a Sport Pilot Rating § 61.193 Flight instructor privileges. A person who...; (e) An aircraft rating; (f) An instrument rating; (g) A flight review, operating privilege, or...

Enclosure enhancement of flight performance

KAUST Repository

Ghommem, Mehdi; Garcia, Daniel; Calo, Victor M.

2014-01-01

We use a potential flow solver to investigate the aerodynamic aspects of flapping flights in enclosed spaces. The enclosure effects are simulated by the method of images. Our study complements previous aerodynamic analyses which considered only the near-ground flight. The present results show that flying in the proximity of an enclosure affects the aerodynamic performance of flapping wings in terms of lift and thrust generation and power consumption. It leads to higher flight efficiency and more than 5% increase of the generation of lift and thrust.

Enclosure enhancement of flight performance

KAUST Repository

Ghommem, Mehdi

2014-08-19

We use a potential flow solver to investigate the aerodynamic aspects of flapping flights in enclosed spaces. The enclosure effects are simulated by the method of images. Our study complements previous aerodynamic analyses which considered only the near-ground flight. The present results show that flying in the proximity of an enclosure affects the aerodynamic performance of flapping wings in terms of lift and thrust generation and power consumption. It leads to higher flight efficiency and more than 5% increase of the generation of lift and thrust.

Data Mining of NASA Boeing 737 Flight Data: Frequency Analysis of In-Flight Recorded Data

Science.gov (United States)

Butterfield, Ansel J.

2001-01-01

Data recorded during flights of the NASA Trailblazer Boeing 737 have been analyzed to ascertain the presence of aircraft structural responses from various excitations such as the engine, aerodynamic effects, wind gusts, and control system operations. The NASA Trailblazer Boeing 737 was chosen as a focus of the study because of a large quantity of its flight data records. The goal of this study was to determine if any aircraft structural characteristics could be identified from flight data collected for measuring non-structural phenomena. A number of such data were examined for spatial and frequency correlation as a means of discovering hidden knowledge of the dynamic behavior of the aircraft. Data recorded from on-board dynamic sensors over a range of flight conditions showed consistently appearing frequencies. Those frequencies were attributed to aircraft structural vibrations.

Oliver E. Buckley Condensed Matter Prize: Emergent gravity from interacting Majorana modes

Science.gov (United States)

Kitaev, Alexei

I will describe a concrete many-body Hamiltonian that exhibits some features of a quantum black hole. The Sachdev-Ye-Kitaev model is a system of N >> 1 Majorana modes that are all coupled by random 4-th order terms. The problem admits an approximate dynamic mean field solution. At low temperatures, there is a fluctuating collective mode that corresponds to reparametrization of time. The effective action for this mode is equivalent to dilaton gravity in two space-time dimensions. Some important questions are how to quantize the reparametrization mode in Lorentzian time, include dissipative effects, and understand this system from the quantum information perspective. Supported by the Simons Foundation, Award Number 376205.

Development and Flight Evaluation of an Emergency Digital Flight Control System Using Only Engine Thrust on an F-15 Airplane

Science.gov (United States)

Burcham, Frank W., Jr.; Maine, Trindel A.; Fullerton, C. Gordon; Webb, Lannie Dean

1996-01-01

A propulsion-controlled aircraft (PCA) system for emergency flight control of aircraft with no flight controls was developed and flight tested on an F-15 aircraft at the NASA Dryden Flight Research Center. The airplane has been flown in a throttles-only manual mode and with an augmented system called PCA in which pilot thumbwheel commands and aircraft feedback parameters were used to drive the throttles. Results from a 36-flight evaluation showed that the PCA system can be used to safety land an airplane that has suffered a major flight control system failure. The PCA system was used to recover from a severe upset condition, descend, and land. Guest pilots have also evaluated the PCA system. This paper describes the principles of throttles-only flight control; a history of loss-of-control accidents; a description of the F-15 aircraft; the PCA system operation, simulation, and flight testing; and the pilot comments.

Theseus Waits on Lakebed for First Flight

Science.gov (United States)

1996-01-01

The Theseus prototype remotely-piloted aircraft (RPA) waits on the lakebed before its first test flight from NASA's Dryden Flight Research Center, Edwards, California, on May 24, 1996. The Theseus aircraft, built and operated by Aurora Flight Sciences Corporation, Manassas, Virginia, was a unique aircraft flown at NASA's Dryden Flight Research Center, Edwards, California, under a cooperative agreement between NASA and Aurora. Dryden hosted the Theseus program, providing hangar space and range safety for flight testing. Aurora Flight Sciences was responsible for the actual flight testing, vehicle flight safety, and operation of the aircraft. The Theseus remotely piloted aircraft flew its maiden flight on May 24, 1996, at Dryden. During its sixth flight on November 12, 1996, Theseus experienced an in-flight structural failure that resulted in the loss of the aircraft. As of the beginning of the year 2000, Aurora had not rebuilt the aircraft. Theseus was built for NASA under an innovative, $4.9 million fixed-price contract by Aurora Flight Sciences Corporation and its partners, West Virginia University, Morgantown, West Virginia, and Fairmont State College, Fairmont, West Virginia. The twin-engine, unpiloted vehicle had a 140-foot wingspan, and was constructed largely of composite materials. Powered by two 80-horsepower, turbocharged piston engines that drove twin 9-foot-diameter propellers, Theseus was designed to fly autonomously at high altitudes, with takeoff and landing under the active control of a ground-based pilot in a ground control station 'cockpit.' With the potential ability to carry 700 pounds of science instruments to altitudes above 60,000 feet for durations of greater than 24 hours, Theseus was intended to support research in areas such as stratospheric ozone depletion and the atmospheric effects of future high-speed civil transport aircraft engines. Instruments carried aboard Theseus also would be able to validate satellite-based global environmental

Integrating Space Flight Resource Management Skills into Technical Lessons for International Space Station Flight Controller Training

Science.gov (United States)

Baldwin, Evelyn

2008-01-01

The Johnson Space Center s (JSC) International Space Station (ISS) Space Flight Resource Management (SFRM) training program is designed to teach the team skills required to be an effective flight controller. It was adapted from the SFRM training given to Shuttle flight controllers to fit the needs of a "24 hours a day/365 days a year" flight controller. More recently, the length reduction of technical training flows for ISS flight controllers impacted the number of opportunities for fully integrated team scenario based training, where most SFRM training occurred. Thus, the ISS SFRM training program is evolving yet again, using a new approach of teaching and evaluating SFRM alongside of technical materials. Because there are very few models in other industries that have successfully tied team and technical skills together, challenges are arising. Despite this, the Mission Operations Directorate of NASA s JSC is committed to implementing this integrated training approach because of the anticipated benefits.

F-14 in banked flight

Science.gov (United States)

1979-01-01

NASA 991, an F-14 Navy Tomcat designated the F-14 (1X), is seen here in banked flight over the desert on a research flight at NASA's Dryden Flight Research Center, Edwards, California. The F-14 was used at Dryden between 1979 and 1985 in extensive high-angle-of-attack and spin-control-and-recovery tests. The NASA/Navy program, which included 212 total flights, acheived considerable improvement in the F-14 high-angle-of-attack flying qualities, improved departure and spin resistance, and contributed to substantial improvements in reducing 'wing rock,' (i.e., tilting from one side to another), at high angles of attack. The Navy had been experiencing inadvertant spin entries caused by the F-14's aileron rudder interconnect. The NASA/Navy/Grumman team developed and tested 4 different configurations of the aileron rudder interconnect to address the spin problem. These problems prompted the Navy to ask the manufacturer, Grumman, and NASA to investigate the issue. NASA 991 had numerous special additions for high-angle-of-attack and spin-recovery research. These included a battery-powered auxiliary power unit, a flight test nose boom, and a special spin recovery system, consisting of forward mounted, hydraulically actuated canards and an emergency spin chute. NASA's F-14 was first flown by NASA research pilots, but was later flown by Grumman, and by Navy test pilots from Patuxent River Naval Air Station (NAS). The Navy test flights with the spin research vehicle constituted the first program that incorporated air combat maneuvering in its test flights at Dryden. The Navy brought F-14s from Point Mugu and Miramar NAS in San Diego to test the new spin control laws in combat situations. Although the new control laws proved valuable, the Navy did not incorporate them into production F-14s until the F-14D, nearly 15 years later.

Design and analysis of advanced flight planning concepts

Science.gov (United States)

Sorensen, John A.

1987-01-01

The objectives of this continuing effort are to develop and evaluate new algorithms and advanced concepts for flight management and flight planning. This includes the minimization of fuel or direct operating costs, the integration of the airborne flight management and ground-based flight planning processes, and the enhancement of future traffic management systems design. Flight management (FMS) concepts are for on-board profile computation and steering of transport aircraft in the vertical plane between a city pair and along a given horizontal path. Flight planning (FPS) concepts are for the pre-flight ground based computation of the three-dimensional reference trajectory that connects the city pair and specifies the horizontal path, fuel load, and weather profiles for initializing the FMS. As part of these objectives, a new computer program called EFPLAN has been developed and utilized to study advanced flight planning concepts. EFPLAN represents an experimental version of an FPS. It has been developed to generate reference flight plans compatible as input to an FMS and to provide various options for flight planning research. This report describes EFPLAN and the associated research conducted in its development.

Simulation model for the Boeing 720B aircraft-flight control system in continuous flight.

Science.gov (United States)

1971-08-01

A mathematical model of the Boeing 720B aircraft and autopilot has been derived. The model is representative of the 720B aircraft for continuous flight within a flight envelope defined by a Mach number of .4 at 20,000 feet altitude in a cruise config...

Flight Test Results for the F-16XL With a Digital Flight Control System

Science.gov (United States)

Stachowiak, Susan J.; Bosworth, John T.

2004-01-01

In the early 1980s, two F-16 airplanes were modified to extend the fuselage length and incorporate a large area delta wing planform. These two airplanes, designated the F-16XL, were designed by the General Dynamics Corporation (now Lockheed Martin Tactical Aircraft Systems) (Fort Worth, Texas) and were prototypes for a derivative fighter evaluation program conducted by the United States Air Force. Although the concept was never put into production, the F-16XL prototypes provided a unique planform for testing concepts in support of future high-speed supersonic transport aircraft. To extend the capabilities of this testbed vehicle the F-16XL ship 1 aircraft was upgraded with a digital flight control system. The added flexibility of a digital flight control system increases the versatility of this airplane as a testbed for aerodynamic research and investigation of advanced technologies. This report presents the handling qualities flight test results covering the envelope expansion of the F-16XL with the digital flight control system.

Reactions of Air Transport Flight Crews to Displays of Weather During Simulated Flight

Science.gov (United States)

Bliss, James P.; Fallon, Corey; Bustamante, Ernesto; Bailey, William R., III; Anderson, Brittany

2005-01-01

Display of information in the cockpit has long been a challenge for aircraft designers. Given the limited space in which to present information, designers have had to be extremely selective about the types and amount of flight related information to present to pilots. The general goal of cockpit display design and implementation is to ensure that displays present information that is timely, useful, and helpful. This suggests that displays should facilitate the management of perceived workload, and should allow maximal situation awareness. The formatting of current and projected weather displays represents a unique challenge. As technologies have been developed to increase the variety and capabilities of weather information available to flight crews, factors such as conflicting weather representations and increased decision importance have increased the likelihood for errors. However, if formatted optimally, it is possible that next generation weather displays could allow for clearer indications of weather trends such as developing or decaying weather patterns. Important issues to address include the integration of weather information sources, flight crew trust of displayed weather information, and the teamed reactivity of flight crews to displays of weather. Past studies of weather display reactivity and formatting have not adequately addressed these issues; in part because experimental stimuli have not approximated the complexity of modern weather displays, and in part because they have not used realistic experimental tasks or participants. The goal of the research reported here was to investigate the influence of onboard and NEXRAD agreement, range to the simulated potential weather event, and the pilot flying on flight crew deviation decisions, perceived workload, and perceived situation awareness. Fifteen pilot-copilot teams were required to fly a simulated route while reacting to weather events presented in two graphical formats on a separate visual display

Enclosure enhancement of flight performance

Directory of Open Access Journals (Sweden)

Mehdi Ghommem

2014-01-01

Full Text Available We use a potential flow solver to investigate the aerodynamic aspects of flapping flights in enclosed spaces. The enclosure effects are simulated by the method of images. Our study complements previous aerodynamic analyses which considered only the near-ground flight. The present results show that flying in the proximity of an enclosure affects the aerodynamic performance of flapping wings in terms of lift and thrust generation and power consumption. It leads to higher flight efficiency and more than 5% increase of the generation of lift and thrust.

Preliminary Flight Results of a Fly-by-throttle Emergency Flight Control System on an F-15 Airplane

Science.gov (United States)

Burcham, Frank W., Jr.; Maine, Trindel A.; Fullerton, C. Gordon; Wells, Edward A.

1993-01-01

A multi-engine aircraft, with some or all of the flight control system inoperative, may use engine thrust for control. NASA Dryden has conducted a study of the capability and techniques for this emergency flight control method for the F-15 airplane. With an augmented control system, engine thrust, along with appropriate feedback parameters, is used to control flightpath and bank angle. Extensive simulation studies were followed by flight tests. The principles of throttles only control, the F-15 airplane, the augmented system, and the flight results including actual landings with throttles-only control are discussed.

X-36 during First Flight

Science.gov (United States)

1997-01-01

The remotely-piloted X-36 Tailless Fighter Agility Research Aircraft climbs out from Rogers Dry Lake at the Dryden Flight Research Center on its first flight in May 1997. The aircraft flew for five minutes and reached an altitude of approximately 4,900 feet. The NASA/Boeing X-36 Tailless Fighter Agility Research Aircraft program successfully demonstrated the tailless fighter design using advanced technologies to improve the maneuverability and survivability of possible future fighter aircraft. The program met or exceeded all project goals. For 31 flights during 1997 at the Dryden Flight Research Center, Edwards, California, the project team examined the aircraft's agility at low speed / high angles of attack and at high speed / low angles of attack. The aircraft's speed envelope reached up to 206 knots (234 mph). This aircraft was very stable and maneuverable. It handled very well. The X-36 vehicle was designed to fly without the traditional tail surfaces common on most aircraft. Instead, a canard forward of the wing was used as well as split ailerons and an advanced thrust-vectoring nozzle for directional control. The X-36 was unstable in both pitch and yaw axes, so an advanced, single-channel digital fly-by-wire control system (developed with some commercially available components) was put in place to stabilize the aircraft. Using a video camera mounted in the nose of the aircraft and an onboard microphone, the X-36 was remotely controlled by a pilot in a ground station virtual cockpit. A standard fighter-type head-up display (HUD) and a moving-map representation of the vehicle's position within the range in which it flew provided excellent situational awareness for the pilot. This pilot-in-the-loop approach eliminated the need for expensive and complex autonomous flight control systems and the risks associated with their inability to deal with unknown or unforeseen phenomena in flight. Fully fueled the X-36 prototype weighed approximately 1,250 pounds. It was 19

Invariant class operators in the decoherent histories analysis of timeless quantum theories

International Nuclear Information System (INIS)

Halliwell, J. J.; Wallden, P.

2006-01-01

The decoherent histories approach to quantum theory is applied to a class of reparametrization-invariant models whose state is an energy eigenstate. A key step in this approach is the construction of class operators characterizing the questions of physical interest, such as the probability of the system entering a given region of configuration space without regard to time. In nonrelativistic quantum mechanics these class operators are given by time-ordered products of projection operators. But in reparametrization-invariant models, where there is no time, the construction of the class operators is more complicated, the main difficulty being to find operators which commute with the Hamiltonian constraint (and so respect the invariance of the theory). Here, inspired by classical considerations, we put forward a proposal for the construction of such class operators for a class of reparametrization-invariant systems. They consist of continuous infinite temporal products of Heisenberg picture projection operators. We investigate the consequences of this proposal in a number of simple models and also compare with the evolving constants method. The formalism developed here is ultimately aimed at cosmological models described by a Wheeler-DeWitt equation, but the specific features of such models are left to future papers

Pegasus hypersonic flight research

Science.gov (United States)

Curry, Robert E.; Meyer, Robert R., Jr.; Budd, Gerald D.

1992-01-01

Hypersonic aeronautics research using the Pegasus air-launched space booster is described. Two areas are discussed in the paper: previously obtained results from Pegasus flights 1 and 2, and plans for future programs. Proposed future research includes boundary-layer transition studies on the airplane-like first stage and also use of the complete Pegasus launch system to boost a research vehicle to hypersonic speeds. Pegasus flight 1 and 2 measurements were used to evaluate the results of several analytical aerodynamic design tools applied during the development of the vehicle as well as to develop hypersonic flight-test techniques. These data indicated that the aerodynamic design approach for Pegasus was adequate and showed that acceptable margins were available. Additionally, the correlations provide insight into the capabilities of these analytical tools for more complex vehicles in which design margins may be more stringent. Near-term plans to conduct hypersonic boundary-layer transition studies are discussed. These plans involve the use of a smooth metallic glove at about the mid-span of the wing. Longer-term opportunities are proposed which identify advantages of the Pegasus launch system to boost large-scale research vehicles to the real-gas hypersonic flight regime.

Writing executable assertions to test flight software

Science.gov (United States)

Mahmood, A.; Andrews, D. M.; Mccluskey, E. J.

1984-01-01

An executable assertion is a logical statement about the variables or a block of code. If there is no error during execution, the assertion statement results in a true value. Executable assertions can be used for dynamic testing of software. They can be employed for validation during the design phase, and exception and error detection during the operation phase. The present investigation is concerned with the problem of writing executable assertions, taking into account the use of assertions for testing flight software. They can be employed for validation during the design phase, and for exception handling and error detection during the operation phase The digital flight control system and the flight control software are discussed. The considered system provides autopilot and flight director modes of operation for automatic and manual control of the aircraft during all phases of flight. Attention is given to techniques for writing and using assertions to test flight software, an experimental setup to test flight software, and language features to support efficient use of assertions.

The Route Analysis Based On Flight Plan

Science.gov (United States)

Feriyanto, Nur; Saleh, Chairul; Fauzi, Achmad; Rachman Dzakiyullah, Nur; Riza Iwaputra, Kahfi

2016-02-01

Economic development effects use of air transportation since the business process in every aspect was increased. Many people these days was prefer using airplane because it can save time and money. This situation also effects flight routes, many airlines offer new routes to deal with competition. Managing flight routes is one of the problems that must be faced in order to find the efficient and effective routes. This paper investigates the best routes based on flight performance by determining the amount of block fuel for the Jakarta-Denpasar flight route. Moreover, in this work compares a two kinds of aircraft and tracks by calculating flight distance, flight time and block fuel. The result shows Jakarta-Denpasar in the Track II has effective and efficient block fuel that can be performed by Airbus 320-200 aircraft. This study can contribute to practice in making an effective decision, especially helping executive management of company due to selecting appropriate aircraft and the track in the flight plan based on the block fuel consumption for business operation.

Flight envelope protection system for unmanned aerial vehicles

KAUST Repository

Claudel, Christian G.

2016-04-28

Systems and methods to protect the flight envelope in both manual flight and flight by a commercial autopilot are provided. A system can comprise: an inertial measurement unit (IMU); a computing device in data communication with the IMU; an application executable by the computing device comprising: logic that estimates an angle of attack; a slip angle; and a speed of an unmanned aerial vehicle (UAV) based at least in part on data received from the UAV. A method can comprise estimating, via a computing device, flight data of a UAV based at least in part on data received from an IMU; comparing the estimated flight data with measured flight data; and triggering an error indication in response to a determination that the measured flight data exceeds a predefined deviation of the estimated flight data. The estimated speed can comprise an estimated airspeed, vertical speed and/or ground velocity.

Helicopter Flight Procedures for Community Noise Reduction

Science.gov (United States)

Greenwood, Eric

2017-01-01

A computationally efficient, semiempirical noise model suitable for maneuvering flight noise prediction is used to evaluate the community noise impact of practical variations on several helicopter flight procedures typical of normal operations. Turns, "quick-stops," approaches, climbs, and combinations of these maneuvers are assessed. Relatively small variations in flight procedures are shown to cause significant changes to Sound Exposure Levels over a wide area. Guidelines are developed for helicopter pilots intended to provide effective strategies for reducing the negative effects of helicopter noise on the community. Finally, direct optimization of flight trajectories is conducted to identify low noise optimal flight procedures and quantify the magnitude of community noise reductions that can be obtained through tailored helicopter flight procedures. Physically realizable optimal turns and approaches are identified that achieve global noise reductions of as much as 10 dBA Sound Exposure Level.

Optical Fiber Assemblies for Space Flight from the NASA Goddard Space Flight Center, Photonics Group

Science.gov (United States)

Ott, Melanie N.; Thoma, William Joe; LaRocca, Frank; Chuska, Richard; Switzer, Robert; Day, Lance

2009-01-01

The Photonics Group at NASA Goddard Space Flight Center in the Electrical Engineering Division of the Advanced Engineering and Technologies Directorate has been involved in the design, development, characterization, qualification, manufacturing, integration and anomaly analysis of optical fiber subsystems for over a decade. The group supports a variety of instrumentation across NASA and outside entities that build flight systems. Among the projects currently supported are: The Lunar Reconnaissance Orbiter, the Mars Science Laboratory, the James Webb Space Telescope, the Express Logistics Carrier for the International Space Station and the NASA Electronic Parts. and Packaging Program. A collection of the most pertinent information gathered during project support over the past year in regards to space flight performance of optical fiber components is presented here. The objective is to provide guidance for future space flight designs of instrumentation and communication systems.

Stroke in Commercial Flights.

Science.gov (United States)

Álvarez-Velasco, Rodrigo; Masjuan, Jaime; DeFelipe, Alicia; Corral, Iñigo; Estévez-Fraga, Carlos; Crespo, Leticia; Alonso-Cánovas, Araceli

2016-04-01

Stroke on board aircraft has been reported in retrospective case series, mainly focusing on economy class stroke syndrome. Data on the actual incidence, pathogenesis, and prognosis of stroke in commercial flights are lacking. A prospective registry was designed to include all consecutive patients referred from an international airport (40 million passengers a year) to our hospital with a diagnosis of ischemic stroke or transient ischemic attack and onset of symptoms during a flight or immediately after landing. Forty-four patients (32 ischemic strokes and 12 transient ischemic attacks) were included over a 76-month period (January 2008 to April 2014). The estimated incidence of stroke was 1 stroke in 35 000 flights. Pathogeneses of stroke or transient ischemic attack were atherothrombotic in 16 (36%), economy class stroke syndrome in 8 (18%), cardioembolic in 7 (16%), arterial dissection in 4 (9%), lacunar stroke in 4 (9%), and undetermined in 5 (12%) patients. Carotid stenosis >70% was found in 12 (27%) of the patients. Overall prognosis was good, and thrombolysis was applied in 44% of the cases. The most common reason for not treating patients who had experienced stroke onset midflight was the delay in reaching the hospital. Only 1 patient with symptom onset during the flight prompted a flight diversion. We found a low incidence of stroke in the setting of air travel. Economy class stroke syndrome and arterial dissection were well represented in our sample. However, the main pathogenesis was atherothrombosis with a high proportion of patients with high carotid stenosis. © 2016 American Heart Association, Inc.

Solar-powered Gossamer Penguin in flight

Science.gov (United States)

1979-01-01

Gossamer Penguin in flight above Rogers Dry Lakebed at Edwards, California, showing the solar panel perpendicular to the wing and facing the sun. Background The first flight of a solar-powered aircraft took place on November 4, 1974, when the remotely controlled Sunrise II, designed by Robert J. Boucher of AstroFlight, Inc., flew following a launch from a catapult. Following this event, AeroVironment, Inc. (founded in 1971 by the ultra-light airplane innovator--Dr. Paul MacCready) took on a more ambitious project to design a human-piloted, solar-powered aircraft. The firm initially took the human-powered Gossamer Albatross II and scaled it down to three-quarters of its previous size for solar-powered flight with a human pilot controlling it. This was more easily done because in early 1980 the Gossamer Albatross had participated in a flight research program at NASA Dryden in a program conducted jointly by the Langley and Dryden research centers. Some of the flights were conducted using a small electric motor for power. Gossamer Penguin The scaled-down aircraft was designated the Gossamer Penguin. It had a 71-foot wingspan compared with the 96-foot span of the Gossamer Albatross. Weighing only 68 pounds without a pilot, it had a low power requirement and thus was an excellent test bed for solar power. AstroFlight, Inc., of Venice, Calif., provided the power plant for the Gossamer Penguin, an Astro-40 electric motor. Robert Boucher, designer of the Sunrise II, served as a key consultant for both this aircraft and the Solar Challenger. The power source for the initial flights of the Gossamer Penguin consisted of 28 nickel-cadmium batteries, replaced for the solar-powered flights by a panel of 3,920 solar cells capable of producing 541 Watts of power. The battery-powered flights took place at Shafter Airport near Bakersfield, Calif. Dr. Paul MacCready's son Marshall, who was 13 years old and weighed roughly 80 pounds, served as the initial pilot for these flights to

Robust Decentralized Formation Flight Control

Directory of Open Access Journals (Sweden)

Zhao Weihua

2011-01-01

Full Text Available Motivated by the idea of multiplexed model predictive control (MMPC, this paper introduces a new framework for unmanned aerial vehicles (UAVs formation flight and coordination. Formulated using MMPC approach, the whole centralized formation flight system is considered as a linear periodic system with control inputs of each UAV subsystem as its periodic inputs. Divided into decentralized subsystems, the whole formation flight system is guaranteed stable if proper terminal cost and terminal constraints are added to each decentralized MPC formulation of the UAV subsystem. The decentralized robust MPC formulation for each UAV subsystem with bounded input disturbances and model uncertainties is also presented. Furthermore, an obstacle avoidance control scheme for any shape and size of obstacles, including the nonapriorily known ones, is integrated under the unified MPC framework. The results from simulations demonstrate that the proposed framework can successfully achieve robust collision-free formation flights.

Eclipse - tow flight closeup and release

Science.gov (United States)

1998-01-01

This clip, running 15 seconds in length, shows the QF-106 'Delta Dart' gear down, with the tow rope secured to the attachment point above the aircraft nose. First there is a view looking back from the C-141A, then looking forward from the nose of the QF-106, and finally a shot of the aircraft being released from the tow rope. NASA Dryden Flight Research Center, Edwards, California, supported a Kelly Space and Technology, Inc. (KST)/U.S. Air Force project known as Eclipse, which demonstrated a reusable tow launch vehicle concept. The purpose of the project was to demonstrate a reusable tow launch vehicle concept that had been conceived and patented by KST. Kelly Space obtained a contract with the USAF Research Laboratory for the tow launch demonstration project under the Small Business Innovation Research (SBIR) program. The USAF SBIR contract included the modifications to turn the QF-106 into the Experimental Demonstrator #1 (EXD-01), and the C141A aircraft to incorporate the tow provisions to link the two aircraft, as well as conducting flight tests. The demonstration consisted of ground and flight tests. These tests included a Combined Systems Test of both airplanes joined by a tow rope, a towed taxi test, and six towed flights. The primary goal of the project was demonstrating the tow phase of the Eclipse concept using a scaled-down tow aircraft (C-141A) and a representative aerodynamically-shaped aircraft (QF-106A) as a launch vehicle. This was successfully accomplished. On December 20, 1997, NASA research pilot Mark Stucky flew a QF-106 on the first towed flight behind an Air Force C-141 in the joint Eclipse project with KST to demonstrate a reusable tow launch vehicle concept developed by KST. Kelly Space and Technology hoped to use the data from the tow tests to validate a tow-to-launch procedure for reusable space launch vehicles. Stucky flew six successful tow tests between December 1997 and February 6, 1998. On February 6, 1998, the sixth and final towed

The invariant charges of the Nambu-Goto theory: Their geometric origin and their completeness

International Nuclear Information System (INIS)

Pohlmeyer, K.; Rehren, K.H.

1988-01-01

We give an alternative construction of the reparametrization invariant 'non-local' conserved charges of the Nambu-Goto theory which elucidates their geometric nature and their completeness property. (orig.)

Development and Flight Test of an Emergency Flight Control System Using Only Engine Thrust on an MD-11 Transport Airplane

Science.gov (United States)

Burcham, Frank W., Jr.; Burken, John J.; Maine, Trindel A.; Fullerton, C. Gordon

1997-01-01

An emergency flight control system that uses only engine thrust, called the propulsion-controlled aircraft (PCA) system, was developed and flight tested on an MD-11 airplane. The PCA system is a thrust-only control system, which augments pilot flightpath and track commands with aircraft feedback parameters to control engine thrust. The PCA system was implemented on the MD-11 airplane using only software modifications to existing computers. Results of a 25-hr flight test show that the PCA system can be used to fly to an airport and safely land a transport airplane with an inoperative flight control system. In up-and-away operation, the PCA system served as an acceptable autopilot capable of extended flight over a range of speeds, altitudes, and configurations. PCA approaches, go-arounds, and three landings without the use of any normal flight controls were demonstrated, including ILS-coupled hands-off landings. PCA operation was used to recover from an upset condition. The PCA system was also tested at altitude with all three hydraulic systems turned off. This paper reviews the principles of throttles-only flight control, a history of accidents or incidents in which some or all flight controls were lost, the MD-11 airplane and its systems, PCA system development, operation, flight testing, and pilot comments.

CFD to Flight: Some Recent Success Stories of X-Plane Design to Flight Test at the NASA Dryden Flight Research Center

Science.gov (United States)

Cosentino, Gary B.

2007-01-01

Several examples from the past decade of success stories involving the design and flight test of three true X-planes will be described: in particular, X-plane design techniques that relied heavily upon computational fluid dynamics (CFD). Three specific examples chosen from the author s personal experience are presented: the X-36 Tailless Fighter Agility Research Aircraft, the X-45A Unmanned Combat Air Vehicle, and, most recently, the X-48B Blended Wing Body Demonstrator Aircraft. An overview will be presented of the uses of CFD analysis, comparisons and contrasts with wind tunnel testing, and information derived from the CFD analysis that directly related to successful flight test. Some lessons learned on the proper application, and misapplication, of CFD are illustrated. Finally, some highlights of the flight-test results of the three example X-planes will be presented. This overview paper will discuss some of the author s experience with taking an aircraft shape from early concept and three-dimensional modeling through CFD analysis, wind tunnel testing, further refined CFD analysis, and, finally, flight. An overview of the key roles in which CFD plays well during this process, and some other roles in which it does not, are discussed. How wind tunnel testing complements, calibrates, and verifies CFD analysis is also covered. Lessons learned on where CFD results can be misleading are also given. Strengths and weaknesses of the various types of flow solvers, including panel methods, Euler, and Navier-Stokes techniques, are discussed. The paper concludes with the three specific examples, including some flight test video footage of the X-36, the X-45A, and the X-48B.

Space Flight Applications of Optical Fiber; 30 Years of Space Flight Success

Science.gov (United States)

Ott, Melanie N.

2010-01-01

For over thirty years NASA has had success with space flight missions that utilize optical fiber component technology. One of the early environmental characterization experiments that included optical fiber was launched as the Long Duration Exposure Facility in 1978. Since then, multiple missions have launched with optical fiber components that functioned as expected, without failure throughout the mission life. The use of optical fiber in NASA space flight communications links and exploration and science instrumentation is reviewed.

14 CFR 121.543 - Flight crewmembers at controls.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Flight crewmembers at controls. 121.543... REQUIREMENTS: DOMESTIC, FLAG, AND SUPPLEMENTAL OPERATIONS Flight Operations § 121.543 Flight crewmembers at controls. (a) Except as provided in paragraph (b) of this section, each required flight crewmember on...

Deep-Space Ka-Band Flight Experience

Science.gov (United States)

Morabito, D. D.

2017-11-01

Lower frequency bands have become more congested in allocated bandwidth as there is increased competition between flight projects and other entities. Going to higher frequency bands offers significantly more bandwidth, allowing for the use of much higher data rates. However, Ka-band is more susceptible to weather effects than lower frequency bands currently used for most standard downlink telemetry operations. Future or prospective flight projects considering deep-space Ka-band (32-GHz) telemetry data links have expressed an interest in understanding past flight experience with received Ka-band downlink performance. Especially important to these flight projects is gaining a better understanding of weather effects from the experience of current or past missions that operated Ka-band radio systems. We will discuss the historical flight experience of several Ka-band missions starting from Mars Observer in 1993 up to present-day deep-space missions such as Kepler. The study of historical Ka-band flight experience allows one to recommend margin policy for future missions. Of particular interest, we will review previously reported-on flight experience with the Cassini spacecraft Ka-band radio system that has been used for radio science investigations as well as engineering studies from 2004 to 2015, when Cassini was in orbit around the planet Saturn. In this article, we will focus primarily on the Kepler spacecraft Ka-band link, which has been used for operational telemetry downlink from an Earth trailing orbit where the spacecraft resides. We analyzed the received Ka-band signal level data in order to characterize link performance over a wide range of weather conditions and as a function of elevation angle. Based on this analysis of Kepler and Cassini flight data, we found that a 4-dB margin with respect to adverse conditions ensures that we achieve at least a 95 percent data return.

Capital flight and political risk

NARCIS (Netherlands)

Lensink, R; Hermes, N; Murinde, [No Value

This paper provides the first serious attempt to examine the relationship between political risk and capital flight for a large set of developing countries. The outcomes of the analysis show that in most cases political risk variables do have a statistically robust relationship to capital flight

STS-70 Post Flight Presentation

Science.gov (United States)

Peterson, Glen (Editor)

1995-01-01

In this post-flight overview, the flight crew of the STS-70 mission, Tom Henricks (Cmdr.), Kevin Kregel (Pilot), Major Nancy Currie (MS), Dr. Mary Ellen Weber (MS), and Dr. Don Thomas (MS), discuss their mission and accompanying experiments. Pre-flight, launch, and orbital footage is followed by the in-orbit deployment of the Tracking and Data Relay Satellite (TDRS) and a discussion of the following spaceborne experiments: a microgravity bioreactor experiment to grow 3D body-like tissue; pregnant rat muscular changes in microgravity; embryonic development in microgravity; Shuttle Amateur Radio Experiment (SAREX); terrain surface imagery using the HERCULES camera; and a range of other physiological tests, including an eye and vision test. Views of Earth include: tropical storm Chantal; the Nile River and Red Sea; lightning over Brazil. A three planet view (Earth, Mars, and Venus) was taken right before sunrise. The end footage shows shuttle pre-landing checkout, entry, and landing, along with a slide presentation of the flight.

14 CFR 31.23 - Flight load factor.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Flight load factor. 31.23 Section 31.23... STANDARDS: MANNED FREE BALLOONS Strength Requirements § 31.23 Flight load factor. In determining limit load, the limit flight load factor must be at least 1.4. ...

14 CFR 91.529 - Flight engineer requirements.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Flight engineer requirements. 91.529...-Powered Multiengine Airplanes and Fractional Ownership Program Aircraft § 91.529 Flight engineer... flight engineer certificate: (1) An airplane for which a type certificate was issued before January 2...

2nd Generation QUATARA Flight Computer Project

Science.gov (United States)

Falker, Jay; Keys, Andrew; Fraticelli, Jose Molina; Capo-Iugo, Pedro; Peeples, Steven

2015-01-01

Single core flight computer boards have been designed, developed, and tested (DD&T) to be flown in small satellites for the last few years. In this project, a prototype flight computer will be designed as a distributed multi-core system containing four microprocessors running code in parallel. This flight computer will be capable of performing multiple computationally intensive tasks such as processing digital and/or analog data, controlling actuator systems, managing cameras, operating robotic manipulators and transmitting/receiving from/to a ground station. In addition, this flight computer will be designed to be fault tolerant by creating both a robust physical hardware connection and by using a software voting scheme to determine the processor's performance. This voting scheme will leverage on the work done for the Space Launch System (SLS) flight software. The prototype flight computer will be constructed with Commercial Off-The-Shelf (COTS) components which are estimated to survive for two years in a low-Earth orbit.

Flight Test of an L(sub 1) Adaptive Controller on the NASA AirSTAR Flight Test Vehicle

Science.gov (United States)

Gregory, Irene M.; Xargay, Enric; Cao, Chengyu; Hovakimyan, Naira

2010-01-01

This paper presents results of a flight test of the L-1 adaptive control architecture designed to directly compensate for significant uncertain cross-coupling in nonlinear systems. The flight test was conducted on the subscale turbine powered Generic Transport Model that is an integral part of the Airborne Subscale Transport Aircraft Research system at the NASA Langley Research Center. The results presented are for piloted tasks performed during the flight test.

In-Flight Validation of a Pilot Rating Scale for Evaluating Failure Transients in Electronic Flight Control Systems

Science.gov (United States)

Kalinowski, Kevin F.; Tucker, George E.; Moralez, Ernesto, III

2006-01-01

Engineering development and qualification of a Research Flight Control System (RFCS) for the Rotorcraft Aircrew Systems Concepts Airborne Laboratory (RASCAL) JUH-60A has motivated the development of a pilot rating scale for evaluating failure transients in fly-by-wire flight control systems. The RASCAL RFCS includes a highly-reliable, dual-channel Servo Control Unit (SCU) to command and monitor the performance of the fly-by-wire actuators and protect against the effects of erroneous commands from the flexible, but single-thread Flight Control Computer. During the design phase of the RFCS, two piloted simulations were conducted on the Ames Research Center Vertical Motion Simulator (VMS) to help define the required performance characteristics of the safety monitoring algorithms in the SCU. Simulated failures, including hard-over and slow-over commands, were injected into the command path, and the aircraft response and safety monitor performance were evaluated. A subjective Failure/Recovery Rating (F/RR) scale was developed as a means of quantifying the effects of the injected failures on the aircraft state and the degree of pilot effort required to safely recover the aircraft. A brief evaluation of the rating scale was also conducted on the Army/NASA CH-47B variable stability helicopter to confirm that the rating scale was likely to be equally applicable to in-flight evaluations. Following the initial research flight qualification of the RFCS in 2002, a flight test effort was begun to validate the performance of the safety monitors and to validate their design for the safe conduct of research flight testing. Simulated failures were injected into the SCU, and the F/RR scale was applied to assess the results. The results validate the performance of the monitors, and indicate that the Failure/Recovery Rating scale is a very useful tool for evaluating failure transients in fly-by-wire flight control systems.

Psychology of Flight Attendant’s Profession

OpenAIRE

Tatyana V. Filipieva

2012-01-01

The profession of a flight attendant appeared in aviation in the 1920s. Professional community of flight attendants is constantly growing with the growth of complexity of aviation technology, professional standards of passenger service and safety. The psychological scientific research was carried out by a psychologist who worked as a flight attendant. The study revealed the psychological content, demands, peculiarities in cabin crews' labor. A job description was accomplished. Temporal and sp...

Range Flight Safety Requirements

Science.gov (United States)

Loftin, Charles E.; Hudson, Sandra M.

2018-01-01

The purpose of this NASA Technical Standard is to provide the technical requirements for the NPR 8715.5, Range Flight Safety Program, in regards to protection of the public, the NASA workforce, and property as it pertains to risk analysis, Flight Safety Systems (FSS), and range flight operations. This standard is approved for use by NASA Headquarters and NASA Centers, including Component Facilities and Technical and Service Support Centers, and may be cited in contract, program, and other Agency documents as a technical requirement. This standard may also apply to the Jet Propulsion Laboratory or to other contractors, grant recipients, or parties to agreements to the extent specified or referenced in their contracts, grants, or agreements, when these organizations conduct or participate in missions that involve range flight operations as defined by NPR 8715.5.1.2.2 In this standard, all mandatory actions (i.e., requirements) are denoted by statements containing the term “shall.”1.3 TailoringTailoring of this standard for application to a specific program or project shall be formally documented as part of program or project requirements and approved by the responsible Technical Authority in accordance with NPR 8715.3, NASA General Safety Program Requirements.

Flight calls and orientation

DEFF Research Database (Denmark)

Larsen, Ole Næsbye; Andersen, Bent Bach; Kropp, Wibke

2008-01-01

flight calls was simulated by sequential computer controlled activation of five loudspeakers placed in a linear array perpendicular to the bird's migration course. The bird responded to this stimulation by changing its migratory course in the direction of that of the ‘flying conspecifics' but after about......  In a pilot experiment a European Robin, Erithacus rubecula, expressing migratory restlessness with a stable orientation, was video filmed in the dark with an infrared camera and its directional migratory activity was recorded. The flight overhead of migrating conspecifics uttering nocturnal...... 30 minutes it drifted back to its original migration course. The results suggest that songbirds migrating alone at night can use the flight calls from conspecifics as additional cues for orientation and that they may compare this information with other cues to decide what course to keep....

14 CFR 121.141 - Airplane flight manual.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Airplane flight manual. 121.141 Section 121... REQUIREMENTS: DOMESTIC, FLAG, AND SUPPLEMENTAL OPERATIONS Manual Requirements § 121.141 Airplane flight manual. (a) Each certificate holder shall keep a current approved airplane flight manual for each type of...

Alpaida (Araneae: Araneidae from the Amazon Basin and Ecuador: new species, new records and complementary descriptions

Directory of Open Access Journals (Sweden)

Regiane Saturnino

2015-06-01

Full Text Available Two new species of Alpaida, A. levii and A. yanayacu, the male of A. iquitos Levi, 1988 and the female of A. gurupi Levi, 1988 are described and illustrated for the first time. Alpaida levii, described from the states of Pará and Amazonas, is closely related to A. delicata (Keyserling, 1892, but differs in that males have a curved and distally pointed terminal apophysis, and females have the epigynum longer than wide and a drop-shaped median lobe. Alpaida yanayacu is only known from Ecuador and is characterized by long and rounded lateral lobes in ventral view and median lobe wide at base. A brief discussion about the morphological similarity among A. levii, A. delicata and A. truncata (Keyserling, 1865 is presented. Based on the information provided, new diagnoses are proposed for A. delicata and A. truncata. New records of A. antonio Levi, 1988, A. bicornuta (Taczanowski, 1878, A. boa Levi, 1988, A. deborae Levi, 1988, A. delicata, A. erythrothorax (Taczanowski, 1873, A. guimaraes Levi, 1988, A. guto Abrahim & Bonaldo, 2008, A. gurupi, A. iquitos, A. leucogramma (White, 1841, A. murtinho Levi, 1988, A. negro Levi, 1988, A. rossi Levi, 1988, A. septemmammata (O. Pickard-Cambridge, 1889, A. simla Levi, 1988, A. tayos Levi, 1988, A. truncata, A. urucuca Levi, 1988, A. utiariti Levi, 1988 and A. veniliae Levi, 1988 are presented.

Optimized Lift for Autonomous Formation Flight

Data.gov (United States)

National Aeronautics and Space Administration — Experimental in-flight evaluations have demonstrated that the concept of formation flight can reduce fuel consumption of trailing aircraft by 10 percent. Armstrong...

Insect flight on fluid interfaces: a chaotic interfacial oscillator

Science.gov (United States)

Mukundarajan, Haripriya; Prakash, Manu

2013-11-01

Flight is critical to the dominance of insect species on our planet, with about 98 percent of insect species having wings. How complex flight control systems developed in insects is unknown, and arboreal or aquatic origins have been hypothesized. We examine the biomechanics of aquatic origins of flight. We recently reported discovery of a novel mode of ``2D flight'' in Galerucella beetles, which skim along an air-water interface using flapping wing flight. This unique flight mode is characterized by a balance between capillary forces from the interface and biomechanical forces exerted by the flapping wings. Complex interactions on the fluid interface form capillary wave trains behind the insect, and produce vertical oscillations at the surface due to non-linear forces arising from deformation of the fluid meniscus. We present both experimental observations of 2D flight kinematics and a dynamic model explaining the observed phenomena. Careful examination of this interaction predicts the chaotic nature of interfacial flight and takeoff from the interface into airborne flight. The role of wingbeat frequency, stroke plane angle and body angle in determining transition between interfacial and fully airborne flight is highlighted, shedding light on the aquatic theory of flight evolution.

Adaptive structures flight experiments

Science.gov (United States)

Martin, Maurice

The topics are presented in viewgraph form and include the following: adaptive structures flight experiments; enhanced resolution using active vibration suppression; Advanced Controls Technology Experiment (ACTEX); ACTEX program status; ACTEX-2; ACTEX-2 program status; modular control patch; STRV-1b Cryocooler Vibration Suppression Experiment; STRV-1b program status; Precision Optical Bench Experiment (PROBE); Clementine Spacecraft Configuration; TECHSAT all-composite spacecraft; Inexpensive Structures and Materials Flight Experiment (INFLEX); and INFLEX program status.

Flight time and flight age in the sweet potato weevil, Cylas formicarius (Fabricius)(Coleoptera: Brentidae)

International Nuclear Information System (INIS)

Shimizu, T.; Moriya, S.

1996-01-01

We examined daily flight patterns and the correlation between adult age and flight in Cylas formicarius in the laboratory at 25 ± 1 ℃ under a 14L10D photoregime by a simple method of counting the number of adults flying out of a cup. The flight activity of males peaked just after the onset of darkness and gradually decreased toward the onset of light. Only a small proportion of them flew during the photophase. More than 90% of male adults flow at least once within 2 weeks after exodus from the sweet potato tuber. The proportion of males flying per day increased to a maximum 1 week after the exodus, and about 10% of them flow even 30 days after the exodus. On the other hand, flight activity of females was low and the proportion of females flying at least once was about 25%. Females flow from 7 to 24 days after the exodus

Flight Activity and Crew Tracking System -

Data.gov (United States)

Department of Transportation — The Flight Activity and Crew Tracking System (FACTS) is a Web-based application that provides an overall management and tracking tool of FAA Airmen performing Flight...

Perseus A in Flight with Moon

Science.gov (United States)

1994-01-01

The Perseus A, a remotely-piloted, high-altitude research aircraft, is seen here framed against the moon and sky during a research mission at the Dryden Flight Research Center, Edwards, California in August 1994. Perseus B is a remotely piloted aircraft developed as a design-performance testbed under NASA's Environmental Research Aircraft and Sensor Technology (ERAST) project. Perseus is one of several flight vehicles involved in the ERAST project. A piston engine, propeller-powered aircraft, Perseus was designed and built by Aurora Flight Sciences Corporation, Manassas, Virginia. The objectives of Perseus B's ERAST flight tests have been to reach and maintain horizontal flight above altitudes of 60,000 feet and demonstrate the capability to fly missions lasting from 8 to 24 hours, depending on payload and altitude requirements. The Perseus B aircraft established an unofficial altitude record for a single-engine, propeller-driven, remotely piloted aircraft on June 27, 1998. It reached an altitude of 60,280 feet. In 1999, several modifications were made to the Perseus aircraft including engine, avionics, and flight-control-system improvements. These improvements were evaluated in a series of operational readiness and test missions at the Dryden Flight Research Center, Edwards, California. Perseus is a high-wing monoplane with a conventional tail design. Its narrow, straight, high-aspect-ratio wing is mounted atop the fuselage. The aircraft is pusher-designed with the propeller mounted in the rear. This design allows for interchangeable scientific-instrument payloads to be placed in the forward fuselage. The design also allows for unobstructed airflow to the sensors and other devices mounted in the payload compartment. The Perseus B that underwent test and development in 1999 was the third generation of the Perseus design, which began with the Perseus Proof-Of-Concept aircraft. Perseus was initially developed as part of NASA's Small High-Altitude Science Aircraft

14 CFR 121.453 - Flight engineer qualifications.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Flight engineer qualifications. 121.453... REQUIREMENTS: DOMESTIC, FLAG, AND SUPPLEMENTAL OPERATIONS Crewmember Qualifications § 121.453 Flight engineer qualifications. (a) No certificate holder may use any person nor may any person serve as a flight engineer on an...

14 CFR 29.673 - Primary flight controls.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Primary flight controls. 29.673 Section 29... AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Design and Construction Control Systems § 29.673 Primary flight controls. Primary flight controls are those used by the pilot for immediate control of pitch, roll...

14 CFR 27.673 - Primary flight control.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Primary flight control. 27.673 Section 27... AIRWORTHINESS STANDARDS: NORMAL CATEGORY ROTORCRAFT Design and Construction Control Systems § 27.673 Primary flight control. Primary flight controls are those used by the pilot for immediate control of pitch, roll...

Differences in the Aerobic Capacity of Flight Muscles between Butterfly Populations and Species with Dissimilar Flight Abilities

Science.gov (United States)

Rauhamäki, Virve; Wolfram, Joy; Jokitalo, Eija; Hanski, Ilkka; Dahlhoff, Elizabeth P.

2014-01-01

Habitat loss and climate change are rapidly converting natural habitats and thereby increasing the significance of dispersal capacity for vulnerable species. Flight is necessary for dispersal in many insects, and differences in dispersal capacity may reflect dissimilarities in flight muscle aerobic capacity. In a large metapopulation of the Glanville fritillary butterfly in the Åland Islands in Finland, adults disperse frequently between small local populations. Individuals found in newly established populations have higher flight metabolic rates and field-measured dispersal distances than butterflies in old populations. To assess possible differences in flight muscle aerobic capacity among Glanville fritillary populations, enzyme activities and tissue concentrations of the mitochondrial protein Cytochrome-c Oxidase (CytOx) were measured and compared with four other species of Nymphalid butterflies. Flight muscle structure and mitochondrial density were also examined in the Glanville fritillary and a long-distance migrant, the red admiral. Glanville fritillaries from new populations had significantly higher aerobic capacities than individuals from old populations. Comparing the different species, strong-flying butterfly species had higher flight muscle CytOx content and enzymatic activity than short-distance fliers, and mitochondria were larger and more numerous in the flight muscle of the red admiral than the Glanville fritillary. These results suggest that superior dispersal capacity of butterflies in new populations of the Glanville fritillary is due in part to greater aerobic capacity, though this species has a low aerobic capacity in general when compared with known strong fliers. Low aerobic capacity may limit dispersal ability of the Glanville fritillary. PMID:24416122

Daedalus - Last Dryden flight

Science.gov (United States)

1988-01-01

The Daedalus 88, with Glenn Tremml piloting, is seen here on its last flight for the NASA Dryden Flight Research Center, Edwards, California. The Light Eagle and Daedalus human powered aircraft were testbeds for flight research conducted at Dryden between January 1987 and March 1988. These unique aircraft were designed and constructed by a group of students, professors, and alumni of the Massachusetts Institute of Technology within the context of the Daedalus project. The construction of the Light Eagle and Daedalus aircraft was funded primarily by the Anheuser Busch and United Technologies Corporations, respectively, with additional support from the Smithsonian Air and Space Museum, MIT, and a number of other sponsors. To celebrate the Greek myth of Daedalus, the man who constructed wings of wax and feathers to escape King Minos, the Daedalus project began with the goal of designing, building and testing a human-powered aircraft that could fly the mythical distance, 115 km. To achieve this goal, three aircraft were constructed. The Light Eagle was the prototype aircraft, weighing 92 pounds. On January 22, 1987, it set a closed course distance record of 59 km, which still stands. Also in January of 1987, the Light Eagle was powered by Lois McCallin to set the straight distance, the distance around a closed circuit, and the duration world records for the female division in human powered vehicles. Following this success, two more aircraft were built, the Daedalus 87 and Daedalus 88. Each aircraft weighed approximately 69 pounds. The Daedalus 88 aircraft was the ship that flew the 199 km from the Iraklion Air Force Base on Crete in the Mediterranean Sea, to the island of Santorini in 3 hours, 54 minutes. In the process, the aircraft set new records in distance and endurance for a human powered aircraft. The specific areas of flight research conducted at Dryden included characterizing the rigid body and flexible dynamics of the Light Eagle, investigating sensors for an

Flight test of the X-29A at high angle of attack: Flight dynamics and controls

Science.gov (United States)

Bauer, Jeffrey E.; Clarke, Robert; Burken, John J.

1995-01-01

The NASA Dryden Flight Research Center has flight tested two X-29A aircraft at low and high angles of attack. The high-angle-of-attack tests evaluate the feasibility of integrated X-29A technologies. More specific objectives focus on evaluating the high-angle-of-attack flying qualities, defining multiaxis controllability limits, and determining the maximum pitch-pointing capability. A pilot-selectable gain system allows examination of tradeoffs in airplane stability and maneuverability. Basic fighter maneuvers provide qualitative evaluation. Bank angle captures permit qualitative data analysis. This paper discusses the design goals and approach for high-angle-of-attack control laws and provides results from the envelope expansion and handling qualities testing at intermediate angles of attack. Comparisons of the flight test results to the predictions are made where appropriate. The pitch rate command structure of the longitudinal control system is shown to be a valid design for high-angle-of-attack control laws. Flight test results show that wing rock amplitude was overpredicted and aileron and rudder effectiveness were underpredicted. Flight tests show the X-29A airplane to be a good aircraft up to 40 deg angle of attack.

Flight Operations . [Zero Knowledge to Mission Complete

Science.gov (United States)

Forest, Greg; Apyan, Alex; Hillin, Andrew

2016-01-01

Outline the process that takes new hires with zero knowledge all the way to the point of completing missions in Flight Operations. Audience members should be able to outline the attributes of a flight controller and instructor, outline the training flow for flight controllers and instructors, and identify how the flight controller and instructor attributes are necessary to ensure operational excellence in mission prep and execution. Identify how the simulation environment is used to develop crisis management, communication, teamwork, and leadership skills for SGT employees beyond what can be provided by classroom training.

The dynamics of parabolic flight: Flight characteristics and passenger percepts

Science.gov (United States)

Karmali, Faisal; Shelhamer, Mark

2008-09-01

Flying a parabolic trajectory in an aircraft is one of the few ways to create freefall on Earth, which is important for astronaut training and scientific research. Here we review the physics underlying parabolic flight, explain the resulting flight dynamics, and describe several counterintuitive findings, which we corroborate using experimental data. Typically, the aircraft flies parabolic arcs that produce approximately 25 s of freefall (0 g) followed by 40 s of enhanced force (1.8 g), repeated 30-60 times. Although passengers perceive gravity to be zero, in actuality acceleration, and not gravity, has changed, and thus we caution against the terms "microgravity" and "zero gravity." Despite the aircraft trajectory including large (45°) pitch-up and pitch-down attitudes, the occupants experience a net force perpendicular to the floor of the aircraft. This is because the aircraft generates appropriate lift and thrust to produce the desired vertical and longitudinal accelerations, respectively, although we measured moderate (0.2 g) aft-ward accelerations during certain parts of these trajectories. Aircraft pitch rotation (average 3°/s) is barely detectable by the vestibular system, but could influence some physics experiments. Investigators should consider such details in the planning, analysis, and interpretation of parabolic-flight experiments.

14 CFR 125.75 - Airplane flight manual.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Airplane flight manual. 125.75 Section 125... OPERATIONS: AIRPLANES HAVING A SEATING CAPACITY OF 20 OR MORE PASSENGERS OR A MAXIMUM PAYLOAD CAPACITY OF 6... Airplane flight manual. (a) Each certificate holder shall keep a current approved Airplane Flight Manual or...

Genetic algorithms coupled with quantum mechanics for refinement of force fields for RNA simulation: a case study of glycosidic torsions in the canonical ribonucleosides.

Science.gov (United States)

Kato, Rodrigo B; Silva, Frederico T; Pappa, Gisele L; Belchior, Jadson C

2015-01-28

We report the use of genetic algorithms (GA) as a method to refine force field parameters in order to determine RNA energy. Quantum-mechanical (QM) calculations are carried out for the isolated canonical ribonucleosides (adenosine, guanosine, cytidine and uridine) that are taken as reference data. In this particular study, the dihedral and electrostatic energies are reparametrized in order to test the proposed approach, i.e., GA coupled with QM calculations. Overall, RMSE comparison with recent published results for ribonucleosides energies shows an improvement, on average, of 50%. Finally, the new reparametrized potential energy function is used to determine the spatial structure of RNA (PDB code ) that was not taken into account in the parametrization process. This structure was improved about 82% comparable with previously published results.

Recent developments in the theory of critical phenomena

International Nuclear Information System (INIS)

Schroer, B.

1974-01-01

The work of Kadanoff, Wilson and Wegner, in the language of Euclidian field theory, is revised. In addition to Wilson's renormalization group method, which is based on the idea of eliminating short range fluctuations, the renormalization method of quantum field theory is discussed, which, in the present context, is called reparametrization (in order to avoid confusion). A reparametrization which is of particular interest in the theory of critical phenomena is the one which leads to scaling equations. New scaling equations which remain free of infrared divergences in two and three dimensions, are derived. The method allows a rather compact and unified discussion of Kadanoff's scaling laws and the related concept of global scaling fields, as well as the scale invariant correlation functions [pt

Bisphosphonate ISS Flight Experiment

Science.gov (United States)

LeBlanc, Adrian; Matsumoto, Toshio; Jones, Jeffrey; Shapiro, Jay; Lang, Thomas; Shackleford, Linda; Smith, Scott M.; Evans, Harlan; Spector, Elizabeth; Ploutz-Snyder, Robert;

Shuttle operations era planning for flight operations

Science.gov (United States)

Holt, J. D.; Beckman, D. A.

1984-01-01

The Space Transportation System (STS) provides routine access to space for a wide range of customers in which cargos vary from single payloads on dedicated flights to multiple payloads that share Shuttle resources. This paper describes the flight operations planning process from payload introduction through flight assignment to execution of the payload objectives and the changes that have been introduced to improve that process. Particular attention is given to the factors that influence the amount of preflight preparation necessary to satisfy customer requirements. The partnership between the STS operations team and the customer is described in terms of their functions and responsibilities in the development of a flight plan. A description of the Mission Control Center (MCC) and payload support capabilities completes the overview of Shuttle flight operations.

Evaluation of Small Unmanned Aircraft Flight Trajectory Accuracy

Directory of Open Access Journals (Sweden)

Ramūnas Kikutis

2014-12-01

Full Text Available Today small unmanned aircraft are being more widely adapted for practical tasks. These tasks require high reliability and flight path accuracy. For such aircraft we have to deal with the chalenge how to compensate external factors and how to ensure the accuracy of the flight trajectory according to new regulations and standards. In this paper, new regulations for the flights of small unmanned aircraft in Lithuanian air space are discussed. Main factors, which affect errors of the autonomous flight path tracking, are discussed too. The emphasis is on the wind factor and the flight path of Dubbin’s trajectories. Research was performed with mathematical-dynamic model of UAV and it was compared with theoretical calculations. All calculations and experiments were accomplished for the circular part of Dubbin’s paths when the airplane was trimmed for circular trajectory flight in calm conditions. Further, for such flight the wind influence was analysed.

Core Flight System Satellite Starter Kit

Data.gov (United States)

National Aeronautics and Space Administration — The Core Flight System Satellite Starter Kit (cFS Kit) will allow a small satellite or CubeSat developer to rapidly develop, deploy, test, and operate flight...

14 CFR 21.37 - Flight test pilot.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Flight test pilot. 21.37 Section 21.37... PROCEDURES FOR PRODUCTS AND PARTS Type Certificates § 21.37 Flight test pilot. Each applicant for a normal... holding an appropriate pilot certificate to make the flight tests required by this part. [Doc. No. 5085...

Preliminary flight test results of a fly-by-throttle emergency flight control system on an F-15 airplane

Science.gov (United States)

Burcham, Frank W., Jr.; Maine, Trindel A.; Fullerton, C. G.; Wells, Edward A.

1993-01-01

A multi-engine aircraft, with some or all of the flight control system inoperative, may use engine thrust for control. NASA Dryden has conducted a study of the capability and techniques for this emergency flight control method for the F-15 airplane. With an augmented control system, engine thrust, along with appropriate feedback parameters, is used to control flightpath and bank angle. Extensive simulation studies have been followed by flight tests. This paper discusses the principles of throttles-only control, the F-15 airplane, the augmented system, and the flight results including landing approaches with throttles-only control to within 10 ft of the ground.

Remotely Piloted Vehicles for Experimental Flight Control Testing

Science.gov (United States)

Motter, Mark A.; High, James W.

2009-01-01

A successful flight test and training campaign of the NASA Flying Controls Testbed was conducted at Naval Outlying Field, Webster Field, MD during 2008. Both the prop and jet-powered versions of the subscale, remotely piloted testbeds were used to test representative experimental flight controllers. These testbeds were developed by the Subsonic Fixed Wing Project s emphasis on new flight test techniques. The Subsonic Fixed Wing Project is under the Fundamental Aeronautics Program of NASA's Aeronautics Research Mission Directorate (ARMD). The purpose of these testbeds is to quickly and inexpensively evaluate advanced concepts and experimental flight controls, with applications to adaptive control, system identification, novel control effectors, correlation of subscale flight tests with wind tunnel results, and autonomous operations. Flight tests and operator training were conducted during four separate series of tests during April, May, June and August 2008. Experimental controllers were engaged and disengaged during fully autonomous flight in the designated test area. Flaps and landing gear were deployed by commands from the ground control station as unanticipated disturbances. The flight tests were performed NASA personnel with support from the Maritime Unmanned Development and Operations (MUDO) team of the Naval Air Warfare Center, Aircraft Division

Biochemical and hematologic changes after short-term space flight

Science.gov (United States)

Leach, C. S.

1992-01-01

Clinical laboratory data from blood samples obtained from astronauts before and after 28 flights (average duration = 6 days) of the Space Shuttle were analyzed by the paired t-test and the Wilcoxon signed-rank test and compared with data from the Skylab flights (duration approximately 28, 59, and 84 days). Angiotensin I and aldosterone were elevated immediately after short-term space flights, but the response of angiotensin I was delayed after Skylab flights. Serum calcium was not elevated after Shuttle flights, but magnesium and uric acid decreased after both Shuttle and Skylab. Creatine phosphokinase in serum was reduced after Shuttle but not Skylab flights, probably because exercises to prevent deconditioning were not performed on the Shuttle. Total cholesterol was unchanged after Shuttle flights, but low density lipoprotein cholesterol increased and high density lipoprotein cholesterol decreased. The concentration of red blood cells was elevated after Shuttle flights and reduced after Skylab flights. Reticulocyte count was decreased after both short- and long-term flights, indicating that a reduction in red blood cell mass is probably more closely related to suppression of red cell production than to an increase in destruction of erythrocytes. Serum ferritin and number of platelets were also elevated after Shuttle flights. In determining the reasons for postflight differences between the shorter and longer flights, it is important to consider not only duration but also countermeasures, differences between spacecraft, and procedures for landing and egress.

Cytogenic Investigations in Flight Personnel

International Nuclear Information System (INIS)

Wolf, G.; Obe, G.; Bergau, L.

1999-01-01

During long-distance flights at high altitudes flight personnel are exposed to cosmic radiation. In order to determine whether there are biological effects of such low dose radiation exposure in aircrew, chromosomal aberrations were investigated in 59 female cabin attendants and a matched control group of 31 members of station personnel. The mean number of dicentric chromosomes amounts to 1.3 (95% CI 1.0-1.6) per 1,000 cells in cabin attendants and 1.4 (95% CI 1.0-1.9) per 1,000 cells in controls. In an additional control group of 56 female clerks from Berlin the mean frequency of dicentric chromosomes was 1.3 (95% CI 1.0-1.6). Neither in dicentric frequency and distribution nor in other aberrations was a significant difference between the groups of flight and station personnel found. The high frequency of multi-aberrant cells was remarkable in flight personnel as well as in station personnel. The reason for this phenomenon is unknown and needs further investigation. (author)

14 CFR 23.673 - Primary flight controls.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Primary flight controls. 23.673 Section 23... Control Systems § 23.673 Primary flight controls. Primary flight controls are those used by the pilot for the immediate control of pitch, roll, and yaw. [Doc. No. 4080, 29 FR 17955, Dec. 18, 1964, as amended...

Positive Exchange of Flight Controls Program

Science.gov (United States)

1995-03-10

This advisory circular provides guidance for all pilots, especially student pilots, flight instructors, and pilot examiners, on the recommended procedure to use for the positive exchange of flight controls between pilots when operating an aircraft.

Biomechanics of optimal flight in ski-jumping.

Science.gov (United States)

Remizov, L P

1984-01-01

The flight in a vertical plane of a ski-jumper after take-off was studied with the purpose of maximising flight distance. To solve the problem of optimal flight (how a jumper must change his angle of attack to obtain the longest jump) the basic theorem of the optimal control theory--Pontriagin's maximum principle--was applied. The calculations were based on data from wind tunnel experiments. It was shown that the maximum flight distance is achieved when the angle of attack is gradually increased according to a convex function the form of which depends on the individual aerodynamic parameters.

NASA Langley's AirSTAR Testbed: A Subscale Flight Test Capability for Flight Dynamics and Control System Experiments

Science.gov (United States)

Jordan, Thomas L.; Bailey, Roger M.

2008-01-01

As part of the Airborne Subscale Transport Aircraft Research (AirSTAR) project, NASA Langley Research Center (LaRC) has developed a subscaled flying testbed in order to conduct research experiments in support of the goals of NASA s Aviation Safety Program. This research capability consists of three distinct components. The first of these is the research aircraft, of which there are several in the AirSTAR stable. These aircraft range from a dynamically-scaled, twin turbine vehicle to a propeller driven, off-the-shelf airframe. Each of these airframes carves out its own niche in the research test program. All of the airplanes have sophisticated on-board data acquisition and actuation systems, recording, telemetering, processing, and/or receiving data from research control systems. The second piece of the testbed is the ground facilities, which encompass the hardware and software infrastructure necessary to provide comprehensive support services for conducting flight research using the subscale aircraft, including: subsystem development, integrated testing, remote piloting of the subscale aircraft, telemetry processing, experimental flight control law implementation and evaluation, flight simulation, data recording/archiving, and communications. The ground facilities are comprised of two major components: (1) The Base Research Station (BRS), a LaRC laboratory facility for system development, testing and data analysis, and (2) The Mobile Operations Station (MOS), a self-contained, motorized vehicle serving as a mobile research command/operations center, functionally equivalent to the BRS, capable of deployment to remote sites for supporting flight tests. The third piece of the testbed is the test facility itself. Research flights carried out by the AirSTAR team are conducted at NASA Wallops Flight Facility (WFF) on the Eastern Shore of Virginia. The UAV Island runway is a 50 x 1500 paved runway that lies within restricted airspace at Wallops Flight Facility. The

JACEE long duration balloon flights

International Nuclear Information System (INIS)

Burnett, T.; Iwai, J.; Lord, J.J.; Strausz, S.; Wilkes, R.J.; Dake, S.; Oda, H.; Miyamura, O.; Fuki, M.; Jones, W.V.; Gregory, J.; Hayashi, T.; Takahashi, U.; Tominaga, Y.; Wefel, J.P.; Fountain, W.; Derrickson, J.; Parnell, T.A.; Roberts, E.; Tabuki, T.; Watts, J.W.

1989-01-01

JACEE balloon-borne emulsion chamber detectors are used to observe the spectra and interactions of cosmic ray protons and nuclei in the energy range 1-100A TeV. Experience with long duration mid-latitude balloon flights and characteristics of the detector system that make it ideal for planned Antarctic balloon flights are discussed. 5 refs., 2 figs

ALOFT Flight Test Report

Science.gov (United States)

1977-10-01

wmmmmmmmmmmmm i ifmu.immM\\]i\\ ßinimm^mmmmviwmmiwui »vimtm twfjmmmmmmi c-f—rmSmn NWC TP 5954 ALOFT Flight Test Report by James D. Ross anrJ I.. M...responsible i"- u conducting the ALOFT Flight Test Program and made contributions to this report: J. Basden , R. ".estbrook, L. Thompson, J. Willians...REPORT DOCUMENTATION PAGE READ INSTRUCTIONS BEFORE COMPLETING FORM 7. AUTMORC«; <oss James D./Xo L. M.y&ohnson IZATION NAME AND ADDRESS Naval

Flight Test of L1 Adaptive Control Law: Offset Landings and Large Flight Envelope Modeling Work

Science.gov (United States)

Gregory, Irene M.; Xargay, Enric; Cao, Chengyu; Hovakimyan, Naira

2011-01-01

This paper presents new results of a flight test of the L1 adaptive control architecture designed to directly compensate for significant uncertain cross-coupling in nonlinear systems. The flight test was conducted on the subscale turbine powered Generic Transport Model that is an integral part of the Airborne Subscale Transport Aircraft Research system at the NASA Langley Research Center. The results presented include control law evaluation for piloted offset landing tasks as well as results in support of nonlinear aerodynamic modeling and real-time dynamic modeling of the departure-prone edges of the flight envelope.

Microgravity Flight: Accommodating Non-Human Primates

Science.gov (United States)

Dalton, Bonnie P.; Searby, Nancy; Ostrach, Louis

1995-01-01

Spacelab Life Sciences-3 (SLS-3) was scheduled to be the first United States man-tended microgravity flight containing Rhesus monkeys. The goal of this flight as in the five untended Russian COSMOS Bion flights and an earlier American Biosatellite flight, was to understand the biomedical and biological effects of a microgravity environment using the non-human primate as human surrogate. The SLS-3/Rhesus Project and COSMOS Primate-BIOS flights all utilized the rhesus monkey, Macaca mulatta. The ultimate objective of all flights with an animal surrogate has been to evaluate and understand biological mechanisms at both the system and cellular level, thus enabling rational effective countermeasures for future long duration human activity under microgravity conditions and enabling technical application to correction of common human physiological problems within earth's gravity, e.g., muscle strength and reloading, osteoporosis, immune deficiency diseases. Hardware developed for the SLS-3/Rhesus Project was the result of a joint effort with the French Centre National d'Etudes Spatiales (CNES) and the United States National Aeronautics and Space Administration (NASA) extending over the last decade. The flight hardware design and development required implementation of sufficient automation to insure flight crew and animal bio-isolation and maintenance with minimal impact to crew activities. A variety of hardware of varying functional capabilities was developed to support the scientific objectives of the original 22 combined French and American experiments, along with 5 Russian co-investigations, including musculoskeletal, metabolic, and behavioral studies. Unique elements of the Rhesus Research Facility (RRF) included separation of waste for daily delivery of urine and fecal samples for metabolic studies and a psychomotor test system for behavioral studies along with monitored food measurement. As in untended flights, telemetry measurements would allow monitoring of

Effect of video-game experience and position of flight stick controller on simulated-flight performance.

Science.gov (United States)

Cho, Bo-Keun; Aghazadeh, Fereydoun; Al-Qaisi, Saif

2012-01-01

The purpose of this study was to determine the effects of video-game experience and flight-stick position on flying performance. The study divided participants into 2 groups; center- and side-stick groups, which were further divided into high and low level of video-game experience subgroups. The experiment consisted of 7 sessions of simulated flying, and in the last session, the flight stick controller was switched to the other position. Flight performance was measured in terms of the deviation of heading, altitude, and airspeed from their respective requirements. Participants with high experience in video games performed significantly better (p increase (0.78 %). However, after switching from a center- to a side-stick controller, performance scores decreased (4.8%).

Commercial air travel and in-flight pulmonary hypertension.

Science.gov (United States)

Smith, Thomas G; Chang, Rae W; Robbins, Peter A; Dorrington, Keith L

2013-01-01

It has recently been shown that commercial air travel triggers hypoxic pulmonary vasoconstriction and modestly increases pulmonary artery pressure in healthy passengers. There is large interindividual variation in hypoxic pulmonary vasoreactivity, and some passengers may be at risk of developing flight-induced pulmonary hypertension, with potentially dangerous consequences. This study sought to determine whether it is possible for a susceptible passenger to develop pulmonary hypertension in response to a routine commercial flight. Using in-flight echocardiography, a passenger was studied during a 6-h commercial flight from London to Dubai. The passenger was generally well and frequently traveled by air, but had been diagnosed with Chuvash polycythemia, a genetic condition that is associated with increased hypoxic pulmonary vasoreactivity. Hematocrit had been normalized with regular venesection. During the flight, arterial oxygen saturation fell to a minimum of 96% and systolic pulmonary artery pressure (sPAP) rapidly increased into the pulmonary hypertensive range. The in-flight increase in sPAP was 50%, reaching a peak of 45 mmHg. This study has established that an asymptomatic but susceptible passenger can rapidly develop in-flight pulmonary hypertension even during a medium-haul flight. Prospective passengers at risk from such responses, including those who have cardiopulmonary disease or increased hypoxic pulmonary vasoreactivity, could benefit from preflight evaluation with a hypoxia altitude simulation test combined with simultaneous echocardiography (HAST-echo). The use of in-flight supplementary oxygen should be considered for susceptible individuals, including all patients diagnosed with Chuvash polycythemia.

Flight testing of a luminescent surface pressure sensor

Science.gov (United States)

Mclachlan, B. G.; Bell, J. H.; Espina, J.; Gallery, J.; Gouterman, M.; Demandante, C. G. N.; Bjarke, L.

1992-01-01

NASA ARC has conducted flight tests of a new type of aerodynamic pressure sensor based on a luminescent surface coating. Flights were conducted at the NASA ARC-Dryden Flight Research Facility. The luminescent pressure sensor is based on a surface coating which, when illuminated with ultraviolet light, emits visible light with an intensity dependent on the local air pressure on the surface. This technique makes it possible to obtain pressure data over the entire surface of an aircraft, as opposed to conventional instrumentation, which can only make measurements at pre-selected points. The objective of the flight tests was to evaluate the effectiveness and practicality of a luminescent pressure sensor in the actual flight environment. A luminescent pressure sensor was installed on a fin, the Flight Test Fixture (FTF), that is attached to the underside of an F-104 aircraft. The response of one particular surface coating was evaluated at low supersonic Mach numbers (M = 1.0-1.6) in order to provide an initial estimate of the sensor's capabilities. This memo describes the test approach, the techniques used, and the pressure sensor's behavior under flight conditions. A direct comparison between data provided by the luminescent pressure sensor and that produced by conventional pressure instrumentation shows that the luminescent sensor can provide quantitative data under flight conditions. However, the test results also show that the sensor has a number of limitations which must be addressed if this technique is to prove useful in the flight environment.

Flight envelope protection system for unmanned aerial vehicles

KAUST Repository

Claudel, Christian G.; Shaqura, Mohammad

2016-01-01

Systems and methods to protect the flight envelope in both manual flight and flight by a commercial autopilot are provided. A system can comprise: an inertial measurement unit (IMU); a computing device in data communication with the IMU

Assessing public exposure in commercial flights in Brazil

Energy Technology Data Exchange (ETDEWEB)

Alves, Vanusa A.; Rochedo, Elaine R.R.; Prado, Nadya M.P.D. [Instituto Militar de Engenharia, Pc. Gen. Tiburcio, 80, Praia Vermelha, Rio de Janeiro, 22290-270 RJ (Brazil); Wasserman, Maria Angelica V. [Instituto de Engenharia Nuclear, Cidade Universitaria, Ilha do Fundao, 21941-906, Rio de Janeiro RJ (Brazil)

2014-07-01

The exposure to cosmic radiation in aircraft travel is higher than at ground level and varies with the year, the latitude, the altitude of flight and the flight time. The aim of this work was to estimate the contribution of cosmic radiation exposure on commercial flights to the Brazilian population. A database, including about 4000 domestic flights was implemented in Excel spreadsheet. The computer program CARI-6, developed by the U.S. Federal Aviation Administration, was used to calculate doses received in each route. Individual effective doses for commercial flights within Brazil ranged from 0.3 to 8.8 μSv, with a total collective annual dose of 312 man Sv. This value is low, about 5 % of the collective dose estimated for domestic flights in US and about 20 % of the collective doses from all flights in UK. This work shall serve as a baseline for future comparisons of exposures due to the growth of civil aviation in the country and open discussions on the concept of risk and its public acceptance, which are relevant aspects for defining radiological protection guidelines. (authors)

Rules for Flight Paths and Time of Flight for Flows in Porous Media with Heterogeneous Permeability and Porosity

Directory of Open Access Journals (Sweden)

Lihua Zuo

2017-01-01

Full Text Available Porous media like hydrocarbon reservoirs may be composed of a wide variety of rocks with different porosity and permeability. Our study shows in algorithms and in synthetic numerical simulations that the flow pattern of any particular porous medium, assuming constant fluid properties and standardized boundary and initial conditions, is not affected by any spatial porosity changes but will vary only according to spatial permeability changes. In contrast, the time of flight along the streamline will be affected by both the permeability and porosity, albeit in opposite directions. A theoretical framework is presented with evidence from flow visualizations. A series of strategically chosen streamline simulations, including systematic spatial variations of porosity and permeability, visualizes the respective effects on the flight path and time of flight. Two practical rules are formulated. Rule  1 states that an increase in permeability decreases the time of flight, whereas an increase in porosity increases the time of flight. Rule  2 states that the permeability uniquely controls the flight path of fluid flow in porous media; local porosity variations do not affect the streamline path. The two rules are essential for understanding fluid transport mechanisms, and their rigorous validation therefore is merited.

String theory on the edge

International Nuclear Information System (INIS)

Thorlacius, L.

1989-01-01

Open string vacuum configurations are described in terms of a one-dimensional field theory on the worldsheet boundary. The one-dimensional path integral has direct physical interpretation as a source term for closed string fields. This means that the vacuum divergences (Mobius infinities) of the path integral must be renormalized correctly. The author shows that reparametrization invariance Ward identities, apart from specifying the equations of motion of spacetime background gauge fields, also serve to fix the renormalization scheme of the vacuum divergences. He argues that vacuum configurations of open strings correspond to Caldeira-Leggett models of dissipative quantum mechanics (DQM) evaluated at a delocalization critical point. This connection reveals that critical DQM will manifest reparametrization invariance (inherited from the conformal invariance of string theory) rather than just scale invariance. This connection should open up new ways of constructing analytic and approximate solutions of open string theory (in particular, topological solitons such as monopoles and instantons). Type I superstring theory gives rise to a supersymmetric boundary field theory. Bose-Fermi cancellation eliminates vacuum divergences but the one-loop beta function remains the same as in the bosonic theory. Reparametrization invariance Ward identities dictate a boundary state normalization which yields consistent string-loop corrections to spacetime equations of motion, in both the periodic and anti-periodic fermion sectors

Integrated Neural Flight and Propulsion Control System

Science.gov (United States)

Kaneshige, John; Gundy-Burlet, Karen; Norvig, Peter (Technical Monitor)

2001-01-01

This paper describes an integrated neural flight and propulsion control system. which uses a neural network based approach for applying alternate sources of control power in the presence of damage or failures. Under normal operating conditions, the system utilizes conventional flight control surfaces. Neural networks are used to provide consistent handling qualities across flight conditions and for different aircraft configurations. Under damage or failure conditions, the system may utilize unconventional flight control surface allocations, along with integrated propulsion control, when additional control power is necessary for achieving desired flight control performance. In this case, neural networks are used to adapt to changes in aircraft dynamics and control allocation schemes. Of significant importance here is the fact that this system can operate without emergency or backup flight control mode operations. An additional advantage is that this system can utilize, but does not require, fault detection and isolation information or explicit parameter identification. Piloted simulation studies were performed on a commercial transport aircraft simulator. Subjects included both NASA test pilots and commercial airline crews. Results demonstrate the potential for improving handing qualities and significantly increasing survivability rates under various simulated failure conditions.

Envelope Protection for In-Flight Ice Contamination

Science.gov (United States)

Gingras, David R.; Barnhart, Billy P.; Ranaudo, Richard J.; Ratvasky, Thomas P.; Morelli, Eugene A.

2010-01-01

Fatal loss-of-control (LOC) accidents have been directly related to in-flight airframe icing. The prototype system presented in this paper directly addresses the need for real-time onboard envelope protection in icing conditions. The combinations of a-priori information and realtime aerodynamic estimations are shown to provide sufficient input for determining safe limits of the flight envelope during in-flight icing encounters. The Icing Contamination Envelope Protection (ICEPro) system has been designed and implemented to identify degradations in airplane performance and flying qualities resulting from ice contamination and provide safe flight-envelope cues to the pilot. Components of ICEPro are described and results from preliminary tests are presented.

Time Manager Software for a Flight Processor

Science.gov (United States)

Zoerne, Roger

2012-01-01

Data analysis is a process of inspecting, cleaning, transforming, and modeling data to highlight useful information and suggest conclusions. Accurate timestamps and a timeline of vehicle events are needed to analyze flight data. By moving the timekeeping to the flight processor, there is no longer a need for a redundant time source. If each flight processor is initially synchronized to GPS, they can freewheel and maintain a fairly accurate time throughout the flight with no additional GPS time messages received. How ever, additional GPS time messages will ensure an even greater accuracy. When a timestamp is required, a gettime function is called that immediately reads the time-base register.

Numerical simulation of hypersonic flight experiment vehicle

OpenAIRE

Yamamoto, Yukimitsu; Yoshioka, Minako; 山本　行光; 吉岡　美菜子

1994-01-01

Hypersonic aerodynamic characteristics of Hypersonic FLight EXperiment (HYFLEX vehicle were investigated by numerical simulations using Navier-Stokes CFD (Computational Fluid Dynamics) code of NAL. Numerical results were compared with experimental data obtained at Hypersonic Wind Tunnel at NAL. In order to investigate real flight aerodynamic characteristics. numerical calculations corresponding to the flight conditions suffering from maximum aero thermodynamic heating were also made and the d...

Development flight tests of JetStar LFC leading-edge flight test experiment

Science.gov (United States)

Fisher, David F.; Fischer, Michael C.

1987-01-01

The overall objective of the flight tests on the JetStar aircraft was to demonstrate the effectiveness and reliability of laminar flow control under representative flight conditions. One specific objective was to obtain laminar flow on the JetStar leading-edge test articles for the design and off-design conditions. Another specific objective was to obtain operational experience on a Laminar Flow Control (LFC) leading-edge system in a simulated airline service. This included operational experience with cleaning requirements, the effect of clogging, possible foreign object damage, erosion, and the effects of ice particle and cloud encounters. Results are summarized.

The Cryogenic Test Bed experiments: Cryogenic heat pipe flight experiment CRYOHP (STS-53). Cryogenic two phase flight experiment CRYOTP (STS-62). Cryogenic flexible diode flight experiment CRYOFD

Science.gov (United States)

Thienel, Lee; Stouffer, Chuck

1995-09-01

This paper presents an overview of the Cryogenic Test Bed (CTB) experiments including experiment results, integration techniques used, and lessons learned during integration, test and flight phases of the Cryogenic Heat Pipe Flight Experiment (STS-53) and the Cryogenic Two Phase Flight Experiment (OAST-2, STS-62). We will also discuss the Cryogenic Flexible Diode Heat Pipe (CRYOFD) experiment which will fly in the 1996/97 time frame and the fourth flight of the CTB which will fly in the 1997/98 time frame. The two missions tested two oxygen axially grooved heat pipes, a nitrogen fibrous wick heat pipe and a 2-methylpentane phase change material thermal storage unit. Techniques were found for solving problems with vibration from the cryo-collers transmitted through the compressors and the cold heads, and mounting the heat pipe without introducing parasitic heat leaks. A thermally conductive interface material was selected that would meet the requirements and perform over the temperature range of 55 to 300 K. Problems are discussed with the bi-metallic thermostats used for heater circuit protection and the S-Glass suspension straps originally used to secure the BETSU PCM in the CRYOTP mission. Flight results will be compared to 1-g test results and differences will be discussed.

The operational flight and multi-crew scheduling problem

Directory of Open Access Journals (Sweden)

Stojković Mirela

2005-01-01

Full Text Available This paper introduces a new kind of operational multi-crew scheduling problem which consists in simultaneously modifying, as necessary, the existing flight departure times and planned individual work days (duties for the set of crew members, while respecting predefined aircraft itineraries. The splitting of a planned crew is allowed during a day of operations, where it is more important to cover a flight than to keep planned crew members together. The objective is to cover a maximum number of flights from a day of operations while minimizing changes in both the flight schedule and the next-day planned duties for the considered crew members. A new type of the same flight departure time constraints is introduced. They ensure that a flight which belongs to several personalized duties, where the number of duties is equal to the number of crew members assigned to the flight, will have the same departure time in each of these duties. Two variants of the problem are considered. The first variant allows covering of flights by less than the planned number of crew members, while the second one requires covering of flights by a complete crew. The problem is mathematically formulated as an integer nonlinear multi-commodity network flow model with time windows and supplementary constraints. The optimal solution approach is based on Dantzig-Wolfe decomposition/column generation embedded into a branch-and-bound scheme. The resulting computational times on commercial-size problems are very good. Our new simultaneous approach produces solutions whose quality is far better than that of the traditional sequential approach where the flight schedule has been changed first and then input as a fixed data to the crew scheduling problem.

On the typography of flight-deck documentation

Science.gov (United States)

Degani, Asaf

1992-01-01

Many types of paper documentation are employed on the flight-deck. They range from a simple checklist card to a bulky Aircraft Flight Manual (AFM). Some of these documentations have typographical and graphical deficiencies; yet, many cockpit tasks such as conducting checklists, way-point entry, limitations and performance calculations, and many more, require the use of these documents. Moreover, during emergency and abnormal situations, the flight crews' effectiveness in combating the situation is highly dependent on such documentation; accessing and reading procedures has a significant impact on flight safety. Although flight-deck documentation are an important (and sometimes critical) form of display in the modern cockpit, there is a dearth of information on how to effectively design these displays. The object of this report is to provide a summary of the available literature regarding the design and typographical aspects of printed matter. The report attempts 'to bridge' the gap between basic research about typography, and the kind of information needed by designers of flight-deck documentation. The report focuses on typographical factors such as type-faces, character height, use of lower- and upper-case characters, line length, and spacing. Some graphical aspects such as layout, color coding, fonts, and character contrast are also discussed. In addition, several aspects of cockpit reading conditions such as glare, angular alignment, and paper quality are addressed. Finally, a list of recommendations for the graphical design of flight-deck documentation is provided.

75 FR 7345 - Filtered Flight Data

Science.gov (United States)

2010-02-19

... digital flight data recorder regulations affecting certain air carriers and operators. This final rule prohibits the filtering of some original flight recorder sensor signals unless a certificate holder can show... A. Verna, Avionics Systems Branch, Aircraft Certification Service, AIR-130, Federal Aviation...

Orion Exploration Flight Test-1 Post-Flight Navigation Performance Assessment Relative to the Best Estimated Trajectory

Science.gov (United States)

Gay, Robert S.; Holt, Greg N.; Zanetti, Renato

2016-01-01

This paper details the post-flight navigation performance assessment of the Orion Exploration Flight Test-1 (EFT-1). Results of each flight phase are presented: Ground Align, Ascent, Orbit, and Entry Descent and Landing. This study examines the on-board Kalman Filter uncertainty along with state deviations relative to the Best Estimated Trajectory (BET). Overall the results show that the Orion Navigation System performed as well or better than expected. Specifically, the Global Positioning System (GPS) measurement availability was significantly better than anticipated at high altitudes. In addition, attitude estimation via processing GPS measurements along with Inertial Measurement Unit (IMU) data performed very well and maintained good attitude throughout the mission.

Liability and Insurance for Suborbital Flights

Science.gov (United States)

Masson-Zwaan, T.

2012-01-01

This paper analyzes and compares liability and liability insurance in the fields of aviation and spaceflight in order to propose solutions for a liability regime and insurance options for suborbital flights. Suborbital flights can be said to take place in the grey zone between air and space, between air law and space law, as well as between aviation insurance and space insurance. In terms of liability, the paper discusses air law and space law provisions in the fields of second and third party liability for damage to passengers and 'innocent bystanders' respectively, touching upon international treaties, national law and EU law, and on insurance to cover those risks. Although the insurance market is currently not ready to provide tailor-made products for operators of suborbital flights, it is expected to adapt rapidly once such flights will become reality. A hybrid approach will provide the best solution in the medium term.

Optimal flight altitude and flight routes with respect to environmental and economical aspects

Energy Technology Data Exchange (ETDEWEB)

Nodorp, D.; Sausen, R.; Land, C. [Deutsche Forschungsanstalt fuer Luft- und Raumfahrt e.V. (DLR), Oberpfaffenhofen (Germany). Inst. fuer Physik der Atmosphaere; Deidewig, F. [Deutsche Forschungsanstalt fuer Luft- und Raumfahrt e.V. (DLR), Koeln (Germany). Inst. fuer Antriebstechnik

1997-12-31

A flight routing method is presented. In addition to conventional minimization of travel time and/or fuel consumption it also takes into account the environmental impact of the aircraft emissions on the climate system. In the process the ECHAM general circulation model is used to trace the pollutants after release, estimate their potential to cause damage and to weight this environmental relative to the economical aspect. Some case studies are presented for an Airbus A340 in the North Atlantic flight corridor. (author) 6 refs.

Optimal flight altitude and flight routes with respect to environmental and economical aspects

Energy Technology Data Exchange (ETDEWEB)

Nodorp, D; Sausen, R; Land, C [Deutsche Forschungsanstalt fuer Luft- und Raumfahrt e.V. (DLR), Oberpfaffenhofen (Germany). Inst. fuer Physik der Atmosphaere; Deidewig, F [Deutsche Forschungsanstalt fuer Luft- und Raumfahrt e.V. (DLR), Koeln (Germany). Inst. fuer Antriebstechnik

1998-12-31

A flight routing method is presented. In addition to conventional minimization of travel time and/or fuel consumption it also takes into account the environmental impact of the aircraft emissions on the climate system. In the process the ECHAM general circulation model is used to trace the pollutants after release, estimate their potential to cause damage and to weight this environmental relative to the economical aspect. Some case studies are presented for an Airbus A340 in the North Atlantic flight corridor. (author) 6 refs.

Morphing Flight Control Surface for Advanced Flight Performance, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — In this SBIR project, a new Morphing Flight Control Surface (MFCS) will be developed. The distinction of the research effort is that the SenAnTech team will employ...

Operations Research Flight Ground Service Education/Outreach

Science.gov (United States)

Smith, Scott M.

2011-01-01

This viewgraph presentation describes a nutritional biochemistry assessment of astronauts in preflight, in-flight, and post-flight operations. In-flight collections of blood and urine samples from astronauts to test the effects of Vitamin K, Pro K, Vitamin D, Omega-3 Fatty Acids, Iron, and Sodium in spaceflight is shown. A demonstration of a 1-carbon metabolism pathway that determines the existence of enzymes and polymorphisms is also presented.

Flight Test Approach to Adaptive Control Research

Science.gov (United States)

Pavlock, Kate Maureen; Less, James L.; Larson, David Nils

2011-01-01

The National Aeronautics and Space Administration s Dryden Flight Research Center completed flight testing of adaptive controls research on a full-scale F-18 testbed. The validation of adaptive controls has the potential to enhance safety in the presence of adverse conditions such as structural damage or control surface failures. This paper describes the research interface architecture, risk mitigations, flight test approach and lessons learned of adaptive controls research.

Comprehensive analysis of transport aircraft flight performance

Science.gov (United States)

Filippone, Antonio

2008-04-01

This paper reviews the state-of-the art in comprehensive performance codes for fixed-wing aircraft. The importance of system analysis in flight performance is discussed. The paper highlights the role of aerodynamics, propulsion, flight mechanics, aeroacoustics, flight operation, numerical optimisation, stochastic methods and numerical analysis. The latter discipline is used to investigate the sensitivities of the sub-systems to uncertainties in critical state parameters or functional parameters. The paper discusses critically the data used for performance analysis, and the areas where progress is required. Comprehensive analysis codes can be used for mission fuel planning, envelope exploration, competition analysis, a wide variety of environmental studies, marketing analysis, aircraft certification and conceptual aircraft design. A comprehensive program that uses the multi-disciplinary approach for transport aircraft is presented. The model includes a geometry deck, a separate engine input deck with the main parameters, a database of engine performance from an independent simulation, and an operational deck. The comprehensive code has modules for deriving the geometry from bitmap files, an aerodynamics model for all flight conditions, a flight mechanics model for flight envelopes and mission analysis, an aircraft noise model and engine emissions. The model is validated at different levels. Validation of the aerodynamic model is done against the scale models DLR-F4 and F6. A general model analysis and flight envelope exploration are shown for the Boeing B-777-300 with GE-90 turbofan engines with intermediate passenger capacity (394 passengers in 2 classes). Validation of the flight model is done by sensitivity analysis on the wetted area (or profile drag), on the specific air range, the brake-release gross weight and the aircraft noise. A variety of results is shown, including specific air range charts, take-off weight-altitude charts, payload-range performance

Electrical Stimulation of Coleopteran Muscle for Initiating Flight.

Directory of Open Access Journals (Sweden)

Hao Yu Choo

Full Text Available Some researchers have long been interested in reconstructing natural insects into steerable robots or vehicles. However, until recently, these so-called cyborg insects, biobots, or living machines existed only in science fiction. Owing to recent advances in nano/micro manufacturing, data processing, and anatomical and physiological biology, we can now stimulate living insects to induce user-desired motor actions and behaviors. To improve the practicality and applicability of airborne cyborg insects, a reliable and controllable flight initiation protocol is required. This study demonstrates an electrical stimulation protocol that initiates flight in a beetle (Mecynorrhina torquata, Coleoptera. A reliable stimulation protocol was determined by analyzing a pair of dorsal longitudinal muscles (DLMs, flight muscles that oscillate the wings. DLM stimulation has achieved with a high success rate (> 90%, rapid response time (< 1.0 s, and small variation (< 0.33 s; indicating little habituation. Notably, the stimulation of DLMs caused no crucial damage to the free flight ability. In contrast, stimulation of optic lobes, which was earlier demonstrated as a successful flight initiation protocol, destabilized the beetle in flight. Thus, DLM stimulation is a promising secure protocol for inducing flight in cyborg insects or biobots.

Flight capital and its reversal for development financing

OpenAIRE

Hermes, Niels; Lensink, Robert; Murinde, Victor

2002-01-01

In this paper, we review the theoretical and empirical literature on capital flight. First, we discuss the measurement of capital flight. Next, we provide information on the magnitude as well as the ‘burden’ of capital flight for a selected set of developing countries in four regions of the world (South Asia, East Asia, Sub-Saharan Africa and Latin America). Moreover, we review the literature on the determinants of capital flight and provide an overview of empirical studies that have analysed...

Crew Factors in Flight Operations X: Alertness Management in Flight Operations

Science.gov (United States)

Rosekind, Mark R.; Gander, Philippa H.; Connell, Linda J.; Co, Elizabeth L.

2001-01-01

In response to a 1980 congressional request, NASA Ames Research Center initiated a Fatigue/Jet Lag Program to examine fatigue, sleep loss, and circadian disruption in aviation. Research has examined fatigue in a variety of flight environments using a range of measures (from self-report to performance to physiological). In 1991, the program evolved into the Fatigue Countermeasures Program, emphasizing the development and evaluation of strategies to maintain alertness and performance in operational settings. Over the years, the Federal Aviation Administration (FAA) has become a collaborative partner in support of fatigue research and other Program activities. From the inception of the Program, a principal goal was to return the information learned from research and other Program activities to the operational community. The objectives of this Education and Training Module are to explain what has been learned about the physiological mechanisms that underlie fatigue, demonstrate the application of this information in flight operations, and offer some specific fatigue countermeasure recommendations. It is intended for all segments of the aeronautics industry, including pilots, flight attendants, managers, schedulers, safety and policy personnel, maintenance crews, and others involved in an operational environment that challenges human physiological capabilities because of fatigue, sleep loss, and circadian disruption.

The hybrid bio-inspired aerial vehicle: Concept and SIMSCAPE flight simulation.

Science.gov (United States)

Tao Zhang; Su, Steven; Nguyen, Hung T

2016-08-01

This paper introduces a Silver Gull-inspired hybrid aerial vehicle, the Super Sydney Silver Gull (SSSG), which is able to vary its structure, under different manoeuvre requirements, to implement three flight modes: the flapping wing flight, the fixed wing flight, and the quadcopter flight (the rotary wing flight of Unmanned Air Vehicle). Specifically, through proper mechanism design and flight mode transition, the SSSG can imitate the Silver Gull's flight gesture during flapping flight, save power consuming by switching to the fixed wing flight mode during long-range cruising, and hover at targeted area when transferring to quadcopter flight mode. Based on the aerodynamic models, the Simscape, a product of MathWorks, is used to simulate and analyse the performance of the SSSG's flight modes. The entity simulation results indicate that the created SSSG's 3D model is feasible and ready to be manufactured for further flight tests.

Pernilla Craig Flight Around Lac Leman

CERN Multimedia

Goldfarb, Steven

2013-01-01

Aviator and future physicist Pernilla Craig visits CERN and is hosted by the Geneva Flight Club. Web pioneer Robert Cailliau helps in the preparations, flight instructor Aline Cosmetatos takes the co-pilot seat, and ATLAS outreach coordinator Steven Goldfarb serves cocktails from the back seat.

14 CFR 61.98 - Flight proficiency.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Flight proficiency. 61.98 Section 61.98 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIRMEN...) Navigation; (viii) Slow flight and stalls; (ix) Emergency operations; and (x) Postflight procedures. (2) For...

14 CFR 61.107 - Flight proficiency.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Flight proficiency. 61.107 Section 61.107 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIRMEN... reference maneuvers; (vii) Navigation; (viii) Slow flight and stalls; (ix) Basic instrument maneuvers; (x...

Psychology of Flight Attendant’s Profession

Directory of Open Access Journals (Sweden)

Tatyana V. Filipieva

2012-01-01

Full Text Available The profession of a flight attendant appeared in aviation in the 1920s. Professionalcommunity of flight attendants is constantly growing with the growth ofcomplexity of aviation technology, professional standards of passenger serviceand safety. The psychological scientific research was carried out by a psychologistwho worked as a flight attendant. The study revealed the psychological content,demands, peculiarities in cabin crews’ labor. A job description was accomplished.Temporal and spatial characteristics, the main contradictions, unfavorable psychogenicand stress factors in labor were examined and described. Psychological profilesof a cabin attendant and of an air passenger were drawn up.

A Trajectory Generation Approach for Payload Directed Flight

Science.gov (United States)

Ippolito, Corey A.; Yeh, Yoo-Hsiu

2009-01-01

Presently, flight systems designed to perform payload-centric maneuvers require preconstructed procedures and special hand-tuned guidance modes. To enable intelligent maneuvering via strong coupling between the goals of payload-directed flight and the autopilot functions, there exists a need to rethink traditional autopilot design and function. Research into payload directed flight examines sensor and payload-centric autopilot modes, architectures, and algorithms that provide layers of intelligent guidance, navigation and control for flight vehicles to achieve mission goals related to the payload sensors, taking into account various constraints such as the performance limitations of the aircraft, target tracking and estimation, obstacle avoidance, and constraint satisfaction. Payload directed flight requires a methodology for accurate trajectory planning that lets the system anticipate expected return from a suite of onboard sensors. This paper presents an extension to the existing techniques used in the literature to quickly and accurately plan flight trajectories that predict and optimize the expected return of onboard payload sensors.

The Effects of Advanced 'Glass Cockpit' Displayed Flight Instrumentation on In-flight Pilot Decision Making

Science.gov (United States)

Steigerwald, John

The Cognitive Continuum Theory (CCT) was first proposed 25 years ago to explain the relationship between intuition and analytical decision making processes. In order for aircraft pilots to make these analytical and intuitive decisions, they obtain information from various instruments within the cockpit of the aircraft. Advanced instrumentation is used to provide a broad array of information about the aircraft condition and flight situation to aid the flight crew in making effective decisions. The problem addressed is that advanced instrumentation has not improved the pilot decision making in modern aircraft. Because making a decision is dependent upon the information available, this experimental quantitative study sought to determine how well pilots organize and interpret information obtained from various cockpit instrumentation displays when under time pressure. The population for this study was the students, flight instructors, and aviation faculty at the Middle Georgia State College School of Aviation campus in Eastman, Georgia. The sample was comprised of two groups of 90 individuals (45 in each group) in various stages of pilot licensure from student pilot to airline transport pilot (ATP). The ages ranged from 18 to 55 years old. There was a statistically significant relationship at the p safety of flight.

Sub-recoil cooling up to nano-Kelvin. Direct measurement of spatial coherency length. New tests for Levy statistics

International Nuclear Information System (INIS)

Saubamea, B.

1998-12-01

This thesis presents a new method to measure the temperature of ultracold atoms from the spatial autocorrelation function of the atomic wave-packets. We thus determine the temperature of metastable helium-4 atoms cooled by velocity selective dark resonance, a method known to cool the atoms below the temperature related to the emission or the absorption of a single photon by an atom at rest, namely the recoil temperature. This cooling mechanism prepares each atom in a coherent superposition of two wave-packets with opposite mean momenta, which are initially superimposed and then drift apart. By measuring the temporal decay of their overlap, we have access to the Fourier transform of the momentum distribution of the atoms. Using this method, we can measure temperatures as low as 5 nK, 800 times as small as the recoil temperature. Moreover we study in detail the exact shape of the momentum distribution and compare the experimental results with two different theoretical approaches: a quantum Monte Carlo simulation and an analytical model based on Levy statistics. We compare the calculated line shape with the one deduced from simulations, and each theoretical model with experimental data. A very good agreement is found with each approach. We thus demonstrate the validity of the statistical model of sub-recoil cooling and give the first experimental evidence of some of its characteristics: the absence of steady-state, the self-similarity and the non Lorentzian shape of the momentum distribution of the cooled atoms. All these aspects are related to the non ergodicity of sub-recoil cooling. (author)

Royalty rules : Alberta producers are now beholden to formal regulations for reporting royalty payments to government levy collectors

International Nuclear Information System (INIS)

Cook, D.

2006-01-01

The Petroleum Marketing Regulation was established by the Alberta Department of Energy in July 2005 in order to clarify the rules governing conventional crude oil royalties. The regulation provides an incentive for industry to comply with the long-existing oil royalty reporting requirements through the addition of non-compliance penalties. An initial shadow billing system has been implemented to give industry the opportunity to understand their responsibilities and implement procedures to correct reporting and delivery inaccuracies. Battery operators in Alberta must now submit a royalty report to the Alberta Petroleum Marketing Commission on a monthly basis. The regulation provides provisions for interest charges on outstanding invoiced amounts, and formalizes existing eligibility requirements for the reimbursement of trucking costs associated with transporting the Crown's share. Penalties will be incurred if royalty reports contain erroneous information, or if the actual deliveries made are less than the prescribed royalty quantity. All penalties levied by the commission will now be sent to the battery operator in a monthly statement. Battery operators who wish to appeal their penalties may do so within 2 months after the date of the monthly statement. It was concluded that industry is not expected to experience any significant problems when the regulation comes into effect, as the 6 month shadow billing period will allow companies to make a smooth transition to the requirements of the new regulation. Details of information sessions for the new regulation were provided, as well as details of various non-compliance penalties. 1 fig

Mouse infection models for space flight immunology

Science.gov (United States)

Chapes, Stephen Keith; Ganta, Roman Reddy; Chapers, S. K. (Principal Investigator)

2005-01-01

Several immunological processes can be affected by space flight. However, there is little evidence to suggest that flight-induced immunological deficits lead to illness. Therefore, one of our goals has been to define models to examine host resistance during space flight. Our working hypothesis is that space flight crews will come from a heterogeneous population; the immune response gene make-up will be quite varied. It is unknown how much the immune response gene variation contributes to the potential threat from infectious organisms, allergic responses or other long term health problems (e.g. cancer). This article details recent efforts of the Kansas State University gravitational immunology group to assess how population heterogeneity impacts host health, either in laboratory experimental situations and/or using the skeletal unloading model of space-flight stress. This paper details our use of several mouse strains with several different genotypes. In particular, mice with varying MHCII allotypes and mice on the C57BL background with different genetic defects have been particularly useful tools with which to study infections by Staphylococcus aureus, Salmonella typhimurium, Pasteurella pneumotropica and Ehrlichia chaffeensis. We propose that some of these experimental challenge models will be useful to assess the effects of space flight on host resistance to infection.

Fused Reality for Enhanced Flight Test Capabilities

Science.gov (United States)

Bachelder, Ed; Klyde, David

2011-01-01

The feasibility of using Fused Reality-based simulation technology to enhance flight test capabilities has been investigated. In terms of relevancy to piloted evaluation, there remains no substitute for actual flight tests, even when considering the fidelity and effectiveness of modern ground-based simulators. In addition to real-world cueing (vestibular, visual, aural, environmental, etc.), flight tests provide subtle but key intangibles that cannot be duplicated in a ground-based simulator. There is, however, a cost to be paid for the benefits of flight in terms of budget, mission complexity, and safety, including the need for ground and control-room personnel, additional aircraft, etc. A Fused Reality(tm) (FR) Flight system was developed that allows a virtual environment to be integrated with the test aircraft so that tasks such as aerial refueling, formation flying, or approach and landing can be accomplished without additional aircraft resources or the risk of operating in close proximity to the ground or other aircraft. Furthermore, the dynamic motions of the simulated objects can be directly correlated with the responses of the test aircraft. The FR Flight system will allow real-time observation of, and manual interaction with, the cockpit environment that serves as a frame for the virtual out-the-window scene.

Flight Qualification of the NASA's Super Pressure Balloon

Science.gov (United States)

Cathey, Henry; Said, Magdi; Fairbrother, Debora

Designs of new balloons to support space science require a number of actual flights under various flight conditions to qualify them to as standard balloon flight offerings to the science community. Development of the new Super Pressure Balloon for the National Aeronautics and Space Administration’s Balloon Program Office has entailed employing new design, analysis, and production techniques to advance the state of the art. Some of these advances have been evolutionary steps and some have been revolutionary steps requiring a maturing understanding of the materials, designs, and manufacturing approaches. The NASA Super Pressure Balloon development end goal is to produce a flight vehicle that is qualified to carry a ton of science instrumentation, at an altitude greater than 33 km while maintaining a near constant pressure altitude for extended periods of up to 100 days, and at any latitude on the globe. The NASA’s Balloon Program Office has pursued this development in a carefully executed incremental approach by gradually increasing payload carrying capability and increasing balloon volume to reach these end goal. A very successful test flight of a ~200,700 m3 balloon was launch in late 2008 from Antarctica. This balloon flew for over 54 days at a constant altitude and circled the Antarctic continent almost three times. A larger balloon was flown from Antarctica in early 2011. This ~422,400 m3 flew at a constant altitude for 22 days making one circuit around Antarctica. Although the performance was nominal, the flight was terminated via command to recover high valued assets from the payload. The balloon designed to reach the program goals is a ~532,200 m3 pumpkin shaped Super Pressure Balloon. A test flight of this balloon was launched from the Swedish Space Corporation’s Esrange Balloon Launch Facilities near Kiruna, Sweden on 14 August, 2012. This flight was another success for this development program. Valuable information was gained from this short test

48 CFR 1852.228-71 - Aircraft flight risks.

Science.gov (United States)

2010-10-01

... 48 Federal Acquisition Regulations System 6 2010-10-01 2010-10-01 true Aircraft flight risks. 1852... 1852.228-71 Aircraft flight risks. (a) As prescribed in 1828.311-2, insert the following clause: Aircraft Flight Risks (DEC 1988) (a) Notwithstanding any other provision of this contract (particularly...

14 CFR 125.363 - Flight release over water.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Flight release over water. 125.363 Section 125.363 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED... Flight release over water. (a) No person may release an airplane for a flight that involves extended...

In-Flight Hypoxemia in a Tracheostomy-Dependent Infant

Directory of Open Access Journals (Sweden)

Jason Quevreaux

2017-01-01

Full Text Available Millions of passengers board commercial flights every year. Healthcare providers are often called upon to treat other passengers during in-flight emergencies. The case presented involves an anesthesia resident treating a tracheostomy-dependent infant who developed hypoxemia on a domestic flight. The patient had an underlying congenital muscular disorder and was mechanically ventilated while at altitude. Although pressurized, cabin barometric pressure while at altitude is less than at sea level. Due to this environment patients with underlying pulmonary or cardiac pathology might not be able to tolerate commercial flight. The Federal Aviation Administration (FAA has mandated a specific set of medical supplies be present on all domestic flights in addition to legislature protecting “Good Samaritan” providers.

Enroute flight-path planning - Cooperative performance of flight crews and knowledge-based systems

Science.gov (United States)

Smith, Philip J.; Mccoy, Elaine; Layton, Chuck; Galdes, Deb

1989-01-01

Interface design issues associated with the introduction of knowledge-based systems into the cockpit are discussed. Such issues include not only questions about display and control design, they also include deeper system design issues such as questions about the alternative roles and responsibilities of the flight crew and the computer system. In addition, the feasibility of using enroute flight path planning as a context for exploring such research questions is considered. In particular, the development of a prototyping shell that allows rapid design and study of alternative interfaces and system designs is discussed.

High Flight. Aerospace Activities, K-12.

Science.gov (United States)

Oklahoma State Dept. of Education, Oklahoma City.

Following discussions of Oklahoma aerospace history and the history of flight, interdisciplinary aerospace activities are presented. Each activity includes title, concept fostered, purpose, list of materials needed, and procedure(s). Topics include planets, the solar system, rockets, airplanes, air travel, space exploration, principles of flight,…

Control-oriented reduced order modeling of dipteran flapping flight

Science.gov (United States)

Faruque, Imraan

Flying insects achieve flight stabilization and control in a manner that requires only small, specialized neural structures to perform the essential components of sensing and feedback, achieving unparalleled levels of robust aerobatic flight on limited computational resources. An engineering mechanism to replicate these control strategies could provide a dramatic increase in the mobility of small scale aerial robotics, but a formal investigation has not yet yielded tools that both quantitatively and intuitively explain flapping wing flight as an "input-output" relationship. This work uses experimental and simulated measurements of insect flight to create reduced order flight dynamics models. The framework presented here creates models that are relevant for the study of control properties. The work begins with automated measurement of insect wing motions in free flight, which are then used to calculate flight forces via an empirically-derived aerodynamics model. When paired with rigid body dynamics and experimentally measured state feedback, both the bare airframe and closed loop systems may be analyzed using frequency domain system identification. Flight dynamics models describing maneuvering about hover and cruise conditions are presented for example fruit flies (Drosophila melanogaster) and blowflies (Calliphorids). The results show that biologically measured feedback paths are appropriate for flight stabilization and sexual dimorphism is only a minor factor in flight dynamics. A method of ranking kinematic control inputs to maximize maneuverability is also presented, showing that the volume of reachable configurations in state space can be dramatically increased due to appropriate choice of kinematic inputs.

GPRsurvey as a part of land-use planning in Levi, Finnish Lapland

Science.gov (United States)

Kupila, Juho

2010-05-01

The need for detailed information regarding overlying soil layers in townplanning areas has become an important issue, especially in certain areas of Finnish Lapland where the lack of usable soil materials is obvious. Use of ground penetrating radar (GPR) is a fast and cost-effective method of determining the structure of subsurface layers and quantity of soil material above the bedrock surface. This environmental project was carried out by the Geological Survey of Finland together with local enterprises, environmental authorities and an EU structural fund. One of the goals of the project was to use GPR to determine the thickness of soil layers and the differences in material above the bedrock level in certain target areas of the project. The study area is located in the municipality of Kittilä, in the center of the Levi ski resort. The study area (total size of 28 hectares) and surroundings are under fast townplanning and there are, for example, plans for a hotel, apartments and underground garages and service routes, thus it is very important to determine the volume of quarrying. As well, the quality and quantity of existing soil is valid data for the reuse of materials and upcoming construction. One drilling program has already been executed in the area (11 boreholes), so GPR profiles were planned based on this drilling data, soil mapping data and data collected from the townplanning map of the area. According to these earlier drillings and soil mapping, most of the soil in the study area was morainic, so the antenna for the GPR-survey was set at 100 MHz. The positioning method used in this project was VRS-GPS (Virtual Reference Station Global Positioning System), which is a very accurate positioning system to use. Accuracy can be as good as a few centimeters. After the GPR-survey, secondary drilling program was carried out according to the GPR-profiles, thus the total amount of collected data from the planning area was 23 boreholes and 3500 meters of GPR

Flight performance of Galileo and Ulysses RTGs

International Nuclear Information System (INIS)

Hemler, R.J.; Kelly, C.E.

1993-01-01

Flight performance data of the GPHS-RTGs (General Purpose Heat Source---Radioisotope Thermoelectric Generators) on the Galileo and Ulysses spacecraft are reported. Comparison of the flight data with analytical predictions is preformed. Differences between actual flight telemetry data and analytical predictions are addressed including the degree of uncertainty associated with the telemetry data. End of mission power level predictions are included for both missions with an overall assessment of RTG mission performances

Core Flight Software

Data.gov (United States)

National Aeronautics and Space Administration — The AES Core Flight Software (CFS) project purpose is to analyze applicability, and evolve and extend the reusability of the CFS system originally developed by...

Space Flight-Associated Neuro-ocular Syndrome.

Science.gov (United States)

Lee, Andrew G; Mader, Thomas H; Gibson, C Robert; Tarver, William

2017-09-01

New and unique physiologic and pathologic systemic and neuro-ocular responses have been documented in astronauts during and after long-duration space flight. Although the precise cause remains unknown, space flight-associated neuro-ocular syndrome (SANS) has been adopted as an appropriate descriptive term. The Space Medicine Operations Division of the US National Aeronautics and Space Administration (NASA) has documented the variable occurrence of SANS in astronauts returning from long-duration space flight on the International Space Station. These clinical findings have included unilateral and bilateral optic disc edema, globe flattening, choroidal and retinal folds, hyperopic refractive error shifts, and nerve fiber layer infarcts. The clinical findings of SANS have been correlated with structural changes on intraorbital and intracranial magnetic resonance imaging and in-flight and terrestrial ultrasonographic studies and ocular optical coherence tomography. Further study of SANS is ongoing for consideration of future manned missions to space, including a return trip to the moon or Mars.

F-15 IFCS Intelligent Flight Control System

Science.gov (United States)

Bosworth, John T.

2008-01-01

This viewgraph presentation gives a detailed description of the F-15 aircraft, flight tests, aircraft performance and overall advanced neural network based flight control technologies for aerospace systems designs.

The Flight of Birds and Other Animals

Directory of Open Access Journals (Sweden)

Colin J. Pennycuick

2015-09-01

Full Text Available Methods of observing birds in flight now include training them to fly under known conditions in wind tunnels, and fitting free-flying birds with data loggers, that are either retrieved or read remotely via satellite links. The performance that comes to light depends on the known limitations of the materials from which they are made, and the conditions in which the birds live. Bird glide polars can be obtained by training birds to glide in a tilting wind tunnel. Translating these curves to power required from the flight muscles in level flight requires drag coefficients to be measured, which unfortunately does not work with bird bodies, because the flow is always fully detached. The drag of bodies in level flight can be determined by observing wingbeat frequency, and shows CD values around 0.08 in small birds, down to 0.06 in small waders specialised for efficient migration. Lift coefficients are up to 1.6 in gliding, or 1.8 for short, temporary glides. In-flight measurements can be used to calculate power curves for birds in level flight, and this has been applied to migrating geese in detail. These typically achieve lift:drag ratios around 15, including allowances for stops, as against 19 for continuous powered flight. The same calculations, applied to Pacific Black-tailed Godwits which start with fat fractions up to 0.55 at departure, show that such birds not only cross the Pacific to New Zealand, but have enough fuel in hand to reach the South Pole if that were necessary. This performance depends on the “dual fuel” arrangements of these migrants, whereby they use fat as their main fuel, and supplement this by extra fuel from burning the engine (flight muscles, as less power is needed later in the flight. The accuracy of these power curves has never been checked, although provision for stopping the bird, and making these checks at regular intervals during a simulated flight was built into the original design of the Lund wind tunnel. The

The quantization of Regge calculus

International Nuclear Information System (INIS)

Rocek, M.; Williams, R.M.; Cambridge Univ.

1984-01-01

We discuss the quantization of Regge's discrete description of Einstein's theory of gravitation. We show how the continuum theory emerges in the weak field long wavelength limit. We also discuss reparametrizations and conformal transformations. (orig.)

DAST in Flight Showing Diverging Wingtip Oscillations

Science.gov (United States)

1980-01-01

Two BQM-34 Firebee II drones were modified with supercritical airfoils, called the Aeroelastic Research Wing (ARW), for the Drones for Aerodynamic and Structural Testing (DAST) program, which ran from 1977 to 1983. In this view of DAST-1 (Serial # 72-1557), taken on June 12, 1980, severe wingtip flutter is visible. Moments later, the right wing failed catastrophically and the vehicle crashed near Cuddeback Dry Lake. Before the drone was lost, it had made two captive and two free flights. Its first free flight, on October 2, 1979, was cut short by an uplink receiver failure. The drone was caught in midair by an HH-3 helicopter. The second free flight, on March 12, 1980, was successful, ending in a midair recovery. The third free flight, made on June 12, was to expand the flutter envelope. All of these missions launched from the NASA B-52. From 1977 to 1983, the Dryden Flight Research Center, Edwards, California, (under two different names) conducted the DAST Program as a high-risk flight experiment using a ground-controlled, pilotless aircraft. Described by NASA engineers as a 'wind tunnel in the sky,' the DAST was a specially modified Teledyne-Ryan BQM-34E/F Firebee II supersonic target drone that was flown to validate theoretical predictions under actual flight conditions in a joint project with the Langley Research Center, Hampton, Virginia. The DAST Program merged advances in electronic remote control systems with advances in airplane design. Drones (remotely controlled, missile-like vehicles initially developed to serve as gunnery targets) had been deployed successfully during the Vietnamese conflict as reconnaissance aircraft. After the war, the energy crisis of the 1970s led NASA to seek new ways to cut fuel use and improve airplane efficiency. The DAST Program's drones provided an economical, fuel-conscious method for conducting in-flight experiments from a remote ground site. DAST explored the technology required to build wing structures with less than