5,198 research outputs found

    Structural interaction with control systems

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    A monograph which assesses the state of the art of space vehicle design and development is presented. The monograph presents criteria and recommended practices for determining the structural data and a mathematical structural model of the vehicle needed for accurate prediction of structure and control-system interaction; for design to minimize undesirable interactions between the structure and the control system; and for determining techniques to achieve the maximum desirable interactions and associated structural design benefits. All space vehicles are treated, including launch vehicles, spacecraft, and entry vehicles. Important structural characteristics which affect the structural model used for structural and control-system interaction analysis are given

    Theoretical dynamic analysis of the landing loads on a vehicle with a tricycle landing gear

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    Theoretical dynamic analysis of landing loads on vehicle with tricycle landing gear compared with X-15 aircraft dat

    Breadboard linear array scan imager using LSI solid-state technology

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    The performance of large scale integration photodiode arrays in a linear array scan (pushbroom) breadboard was evaluated for application to multispectral remote sensing of the earth's resources. The technical approach, implementation, and test results of the program are described. Several self scanned linear array visible photodetector focal plane arrays were fabricated and evaluated in an optical bench configuration. A 1728-detector array operating in four bands (0.5 - 1.1 micrometer) was evaluated for noise, spectral response, dynamic range, crosstalk, MTF, noise equivalent irradiance, linearity, and image quality. Other results include image artifact data, temporal characteristics, radiometric accuracy, calibration experience, chip alignment, and array fabrication experience. Special studies and experimentation were included in long array fabrication and real-time image processing for low-cost ground stations, including the use of computer image processing. High quality images were produced and all objectives of the program were attained

    Chocolat noir ou chocolat blanc? Le cacao et la santé cardiovasculaire

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    Epidemiological data show that a regular dietary intake of plant-derived foods reduces the risk of cardiovascular disease. Recent research indeed demonstrates interesting data about cocoa consumption, with high concentrations of polyphenols, and beneficial effects on blood pressure, insulin resistance and platelet function. Although still debated, a range of potential mechanisms through which cocoa might exert their benefits on cardiovascular health have been suggested: activation of nitric oxide, antioxidant, anti-inflammatory, anti-platelet effects, which might in turn improve endothelial function, lipid levels, blood pressure and insulin resistance. This article reviews available data about the effects of the consumption of cocoa and different types of chocolate on cardiovascular health, and outlines potential mechanisms involved on the basis of recent studies

    Renovation housing: analysis methods and evaluation of investment projects

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    The article discusses the problem of providing the population of any country affordable and comfortable housing is key in ensuring sustainable economic development. The author has been compiled a statistical analysis of the need for housing renovation in the Tomsk region. The high capital investment projects in this field it seems necessary to look for new sources of funding, as well as pre-assess their effectiveness

    Zenith-Distance Dependence of Chromatic Shear Effect: A Limiting Factor for an Extreme Adaptive Optics System

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    Consider a perfect AO system with a very fine wavefront sampling interval and a very small actuator interval. If this AO system senses wavefront at a wavelength, lambda_{WFS}, and does science imaging at another wavelength, lambda_{SCI}, the light paths through the turbulent atmosphere at these two wavelengths are slightly different for a finite zenith distance, z. The error in wavefront reconstruction of the science channel associated with this non-common path effect, or so-called chromatic shear, is uncorrectable and sets an upper bound of the system performance. We evaluate the wavefront variance, sigma^2(lambda_{WFS},lambda_{SCI},z) for a typical seeing condition at Mauna Kea and find that this effect is not negligible at a large z. If we require that the Strehl ratio be greater than 99 or 95%, z must be less than about 50 or 60 deg respectively, for the combination of visible wavefront sensing and infrared science imaging.Comment: To appear in 2006/12/01 issue of Ap

    The abundances of ethane to acetylene in the atmospheres of Jupiter and Saturn

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    The present determination of the stratospheric abundances of ethane and acetylene on Jupiter and Saturn on the basis of IR spectra near 780/cm uses atmospheric models whose thermal and density profiles have constant mixing ratios. The ratio of ethane to acetylene is noted to be insensitive to model atmosphere assumptions; it is 55 + or - 31 for Jupiter and 23 + or - 12 where model mixing ratios are uniform. Atmospheric model density profiles adapted from theoretical photochemical models are noted to also yield a higher ethane/acetylene ratios for Jupiter

    Towards Erlang Verification by Term Rewriting

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    The final publication is available at Springer via http://dx.doi.org/10.1007/978-3-319-14125-1_7This paper presents a transformational approach to the verification of Erlang programs. We define a stepwise transformation from (first-order) Erlang programs to (non-deterministic) term rewrite systems that compute an overapproximation of the original Erlang program. In this way, existing techniques for term rewriting become available. Furthermore, one can use narrowing as a symbolic execution extension of rewriting in order to design a verification technique. We illustrate our approach with some examples, including a deadlock analysis of a simple Erlang program.Vidal Oriola, GF. (2013). Towards Erlang Verification by Term Rewriting. En Logic-Based Program Synthesis and Transformation. Springer. 109-126. doi:10.1007/978-3-319-14125-1_7S109126Albert, E., Arenas, P., Gómez-Zamalloa, M.: Symbolic Execution of Concurrent Objects in CLP. In: Russo, C., Zhou, N.-F. (eds.) PADL 2012. LNCS, vol. 7149, pp. 123–137. Springer, Heidelberg (2012)Albert, E., Vidal, G.: The narrowing-driven approach to functional logic program specialization. New Generation Computing 20(1), 3–26 (2002)Joe, A., Robert, V., Williams, M.: Concurrent programming in ERLANG. Prentice Hall (1993)Arts, T., Earle, C.B., Derrick, J.: Development of a verified Erlang program for resource locking. STTT 5(2–3), 205–220 (2004)Baader, F., Nipkow, T.: Term Rewriting and All That. Cambridge University Press (1998)Caballero, R., Martin-Martin, E., Riesco, A., Tamarit, S.: A Declarative Debugger for Sequential Erlang Programs. In: Veanes, M., Viganò, L. (eds.) TAP 2013. LNCS, vol. 7942, pp. 96–114. Springer, Heidelberg (2013)Claessen, K., Svensson, H.: A semantics for distributed Erlang. In: Sagonas, K.F., Armstrong, J. (eds.). In: Proc. of the 2005 ACM SIGPLAN Workshop on Erlang, pp. 78–87. ACM (2005)Earle, C.B.: Symbolic program execution using the Erlang verification tool. In: Alpuente, M. (eds.) Proc. of the 9th International Workshop on Functional and Logic Programming (WFLP 2000), pp. 42–55 (2000)Felleisen, M., Friedman, D.P., Kohlbecker, E.E., Duba, B.F.: A syntactic theory of sequential control. Theor. Comput. Sci. 52, 205–237 (1987)Fredlund, L.-A., Svensson, H.: McErlang: a model checker for a distributed functional programming language. In: Hinze, R., Ramsey, N. (eds). In: Proc. of ICFP 2007, pp. 125–136. ACM (2007)Giesl, J., Arts, T.: Verification of Erlang Processes by Dependency Pairs. Appl. Algebra Eng. Commun. Comput. 12(1/2), 39–72 (2001)Hanus, M. (ed.): Curry: An integrated functional logic language (vers. 0.8.3) (2012), http://www.curry-language.orgHuch, F.: Verification of Erlang Programs using Abstract Interpretation and Model Checking. In: Rémi, D., Lee, P. (eds.) Proc. of ICFP 1999, pp. 261–272. ACM (1999)J.-M., H.: Canonical forms and unification. In: Bibel, W., Kowalski, R. (eds.) 5th Conference on Automated Deduction Les Arcs. LNCS, pp. 318–334. Springer, Heidelberg (1980)Leucker, M., Noll, T.: Rewriting Logic as a Framework for Generic Verification Tools. Electr. Notes Theor. Comput. Sci. 36, 121–137 (2000)Meseguer, J.: Conditioned Rewriting Logic as a United Model of Concurrency. Theor. Comput. Sci. 96(1), 73–155 (1992)Neuhäußer, M.R., Noll, T.: Abstraction and Model Checking of Core Erlang Programs in Maude. Electr. Notes Theor. Comput. Sci. 176(4), 147–163 (2007)Nishida, N., Vidal, G.: A finite representation of the narrowing space. In: Proc. of the 23th International Symposium on Logic-Based Program Synthesis and Transformation (LOPSTR 2013). Technical Report TR-11-13, Universidad Complutense de Madrid, pp. 113–128 (To appear in Springer LNCS, 2013). http://users.dsic.upv.es/~gvidal/Noll, T.: A Rewriting Logic Implementation of Erlang. Electr. Notes Theor. Comput. Sci. 44(2), 206–224 (2001)Noll, T.: Equational Abstractions for Model Checking Erlang Programs. Electr. Notes Theor. Comput. 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    Not in my back yard! Sports stadia location and the property market

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    In recent years sports stadia have been built in the UK, not only for their intended sporting purpose but with the twin aim of stimulating economic and physical regeneration. However, proposals to locate stadia in urban areas often prompt a negative reaction from local communities, fearing a decline in property prices. This paper will use a case study of the Millennium Stadium in Cardiff and the City of Manchester Stadium to illustrate that in contrast to this widely held belief, sports stadia can actually enhance the value of residential property. Furthermore, it will argue that stadia also contribute indirectly to property value through the creation of pride, confidence and enhanced image of an area.</p
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