Cruise noise of the 2/9th scale model of the Large-scale Advanced Propfan (LAP) propeller, SR-7A

Noise data on the Large-scale Advanced Propfan (LAP) propeller model SR-7A were taken in the NASA Lewis Research Center 8 x 6 foot Wind Tunnel. The maximum blade passing tone noise first rises with increasing helical tip Mach number to a peak level, then remains the same or decreases from its peak level when going to higher helical tip Mach numbers. This trend was observed for operation at both constant advance ratio and approximately equal thrust. This noise reduction or, leveling out at high helical tip Mach numbers, points to the use of higher propeller tip speeds as a possible method to limit airplane cabin noise while maintaining high flight speed and efficiency. Projections of the tunnel model data are made to the full scale LAP propeller mounted on the test bed aircraft and compared with predictions. The prediction method is found to be somewhat conservative in that it slightly overpredicts the projected model data at the peak

A population-based case-control study on social factors and risk of testicular germ cell tumours

Objectives Incidence rates for testicular cancer have risen over the last few decades. Findings of an association between the risk of testicular cancer and social factors are controversial. The association of testicular cancer and different indicators of social factors were examined in this study.<p></p> Design Case–control study.<p></p> Setting Population-based multicentre study in four German regions (city states Bremen and Hamburg, the Saarland region and the city of Essen).<p></p> Participants The study included 797 control participants and 266 participants newly diagnosed with testicular cancer of which 167 cases were classified as seminoma and 99 as non-seminoma. The age of study participants ranged from 15 to 69 years.<p></p> Methods Social position was classified by educational attainment level, posteducational training, occupational sectors according to Erikson-Goldthorpe-Portocarrero (EGP) and the socioeconomic status (SES) on the basis of the International SocioEconomic Index of occupational status (ISEI). ORs and corresponding 95% CIs (95% CIs) were calculated for the whole study sample and for seminoma and non-seminoma separately.<p></p> Results Testicular cancer risk was modestly increased among participants with an apprenticeship (OR=1.7 (95% CI 1.0 to 2.8)) or a university degree (OR=1.6 (95% CI 0.9 to 2.8)) relative to those whose education was limited to school. Analysis of occupational sectors revealed an excess risk for farmers and farm-related occupations. No clear trend was observed for the analyses according to the ISEI-scale.<p></p> Conclusions Social factors based on occupational measures were not a risk factor for testicular cancer in this study. The elevated risk in farmers and farm-related occupations warrants further research including analysis of occupational exposures.<p></p&gt

Computing the lower and upper bounds of Laplace eigenvalue problem: by combining conforming and nonconforming finite element methods

This article is devoted to computing the lower and upper bounds of the Laplace eigenvalue problem. By using the special nonconforming finite elements, i.e., enriched Crouzeix-Raviart element and extension $Q_1^{\rm rot}$, we get the lower bound of the eigenvalue. Additionally, we also use conforming finite elements to do the postprocessing to get the upper bound of the eigenvalue. The postprocessing method need only to solve the corresponding source problems and a small eigenvalue problem if higher order postprocessing method is implemented. Thus, we can obtain the lower and upper bounds of the eigenvalues simultaneously by solving eigenvalue problem only once. Some numerical results are also presented to validate our theoretical analysis.Comment: 19 pages, 4 figure

Hybrid fiber reinforcement and crack formation in cementitious composite materials

The use of different types of fibers simultaneously for reinforcing cementitious matrices is motivated by the concept of a multi-scale nature of the crack propagation process. Fibers with different geometrical and mechanical properties are used to bridge cracks of different sizes from the micro- to the macroscale. In this study, the performance of different fiber reinforced cementitious composites is assessed in terms of their tensile stress-crack opening behavior. The results obtained from this investigation allow a direct quantitative comparison of the behavior obtained from the different fiber reinforcement systems. The research described in this paper shows that the multi-scale conception of cracking and the use of hybrid fiber reinforcements do not necessarily result in an improved tensile behavior of the composite. Particular material design requirements may nevertheless justify the use of hybrid fiber reinforcements.Fundação para a Ciência e a Tecnologia (FCT) - SFRH / BD / 36515 / 200

Supramolecular chemistry and molecular design: self-assembly of molecular squares

Journal ArticleModem supramolecular chemistry has been described as organized polymolecular systems held together by noncovalent interactions and represents one of the major frontiers in the chemical sciences.'-' At present the field is dominated by the hydrogen bonding motif that mimics biological systems and the classical covalent macrocyclics such as crown ethers, cyclophanes, cyclodextrins, calixarenes, etc., that represent the roots of the field!?' Much less is known about the use of coordination and transition metals as a motif for the assembly of supramolecular species

Getting Acquainted with Kant

My question here concerns whether Kant claims that experience has nonconceptual content, or whether, on his view, experience is essentially conceptual. However there is a sense in which this debate concerning the content of intuition is ill-conceived. Part of this has to do with the terms in which the debate is set, and part to do with confusion over the connection between Kant’s own views and contemporary concerns in epistemology and the philosophy of mind. However, I think much of the substance of the debate concerning Kant’s views on the content of experience can be salvaged by reframing it in terms of a debate about the dependence relations, if any, that exist between different cognitive capacities. Below, in Section 2, I clarify the notion of ‘content’ I take to be at stake in the interpretive debate. Section 3 presents reasons for thinking that intuition cannot have content in the relevant sense. I then argue, in Section 4, that the debate be reframed in terms of dependence. We should distinguish between Intellectualism, according to which all objective representation (understood in a particular way) depends on acts of synthesis by the intellect, and Sensibilism, according to which at least some forms of objective representation are independent of any such acts (or the capacity for such acts). Finally, in Section 5, I further elucidate the cognitive role of intuition. I articulate a challenge which Kant understands alethic modal considerations to present for achieving cognition, and argue that a version of Sensibilism that construes intuition as a form of acquaintance is better positioned to answer this challenge than Intellectualism

Coupled hygrothermal, electrochemical, and mechanical modelling for deterioration prediction in reinforced cementitious materials

In this paper a coupled hygrothermal, electrochemical, and mechanical modelling approach for the deterioration prediction in cementitious materials is briefly outlined. Deterioration prediction is thereby based on coupled modelling of (i) chemical processes including among others transport of heat and matter as well as phase assemblage on the nano and micro scale, (ii) corrosion of steel including electrochemical processes at the reinforcement surface, and (iii) material performance including corrosion- and load-induced damages on the meso and macro scale. The individual FEM models are fully coupled, i.e. information, such as such as corrosion current density, damage state of concrete cover, etc., are constantly exchanged between the models

Fruit crops, 1980: a summary of research

Performance of selected apple cultivars on semi-standard rootstocks in southern Ohio / David C. Ferree, Donald A. Chandler, and John C. Schmid -- Influence of summer pruning and alar on growth, flowering, and fruit set of Jerseymac apple trees / D. C. Ferree and E. J. Stang -- Influence of promalin on Delicious in Ohio / D. C. Ferree, E. J. Stang and R. C. Funt -- The effects of overtree misting for bloom delay on soil water status, net photosynthesis, transpiration, and carbohydrate levels of apple trees / R. M. Crassweller and D. C. Ferree -- Effect of orchard heaters on vertical temperature profiles / R. D. Fox, R. D. Brazee, and D. C. Ferree -- The effect of orchard heaters on air movement and temperature / R. D. Fox, R. D. Brazee, and D. C. Ferree -- Organotins and mite control on apples in Ohio / Franklin R. Hall -- Model of the air sprayer / R. D. Fox, R. D. Brazee, D. L. Reichard and F. R. Hall -- Effects of application equipment variables on spray deposition by orchard air sprayers / D. L. Reichard, F. R. Hall and H. R. Krueger -- Fungi associated with moldy-core of apple and their location within fruit / Michael A. Ellis -- Nutrient content of twelve french and american hybrid grape cultivars grown under a wide range of soil conditions / Garth A. Cahoo

Torsion Tests of Tubes

This report presents the results of tests of 63 chromium-molybdenum steel tubes and 102 17st aluminum-alloy tubes of various sizes and lengths made to study the dependence of the torsional strength on both the dimensions of the tube and the physical properties of the tube material. Three types of failure are found to be important for sizes of tubes frequently used in aircraft construction: (1) failure by plastic shear, in which the tube material reached its yield strength before the critical torque was reached; (2) failure by elastic two-lobe buckling, which depended only on the elastic properties of the tube material and the dimensions of the tube; and (3) failure by a combination of (1) and (2) that is, by buckling taking place after some yielding of the tube material