42,783 research outputs found
Active controls technology to maximize structural efficiency
The implication of the dependence on active controls technology during the design phase of transport structures is considered. Critical loading conditions are discussed along with probable ways of alleviating these loads. Why fatigue requirements may be critical and can only be partially alleviated is explained. The significance of certain flutter suppression system criteria is examined
Summer Workshop on Near-Earth Resources
The possible large scale use of extraterrestrial resources was addressed, either to construct structures in space or to return to Earth as supplements for terrestrial resources. To that end, various specific recommendations were made by the participants in the summer study on near-Earth resources, held at La Jolla, California, 6 to 13 August, 1977. The Moon and Earth-approaching asteroids were considered. Summaries are included of what is known about their compositions and what needs to be learned, along with recommendations for missions designed to provide the needed data. Tentative schedules for these projects are also offered
Uranium(III) coordination chemistry and oxidation in a flexible small-cavity macrocycle
U(III) complexes of the conformationally flexible, small-cavity macrocycle trans-calix[2]benzene[2]pyrrolide (L)2–, [U(L)X] (X = O-2,6-tBu2C6H3, N(SiMe3)2), have been synthesized from [U(L)BH4] and structurally characterized. These complexes show binding of the U(III) center in the bis(arene) pocket of the macrocycle, which flexes to accommodate the increase in the steric bulk of X, resulting in long U–X bonds to the ancillary ligands. Oxidation to the cationic U(IV) complex [U(L)X][B(C6F5)4] (X = BH4) results in ligand rearrangement to bind the smaller, harder cation in the bis(pyrrolide) pocket, in a conformation that has not been previously observed for (L)2–, with X located between the two ligand arene rings
Industries and the bank lending effects of bank credit demand and monetary policy in Germany
This paper presents evidence on the industry effects of bank lending in Germany and identifies the industry effects of bank lending associated with changes in monetary policy and industryspecific bank credit demand. To this end, we estimate individual bank lending functions for 13 manufacturing and non-manufacturing industries and five banking groups using quarterly bank balance sheet and bank lending data for the period 1992:1-2002:4. The evidence from dynamic panel data models shows that industry-specific bank lending growth predominantly responds to changes in industry-specific bank credit demand rather than to changes in monetary policy. In fact, conclusions regarding the bank lending effects of monetary policy are very sensitive to the choice of industry. The empirical results lend strong support to the existence of industry effects of bank lending. Because industries are a prominent source of variation in the bank lending effects of bank credit demand and monetary policy, the paper concludes that the industry composition of bank credit portfolios is an important determinant of bank lending growth and monetary policy effectiveness. --Monetary policy transmission,credit channel,industry structure,dynamic panel data
Vision and Reading Difficulties Part 5: Clinical protocol and the role of the eye-care practitioner
This series of articles has described various aspects of visual characteristics of reading difficulties and the background behind techniques such as the use of coloured filters in helping to reduce the difficulties that are experienced. The present article, which is the last in series, aims to describe a clinical protocol that can be used by the busy eye care practitioner for the investigation and management of such patients. It also describes the testing techniques that can be used for the various assessments. Warning: DO NOT LOOK AT FIGURE 7 IF YOU HAVE MIGRAINE OR EPILEPSY
Weak-triplet, color-octet scalars and the CDF dijet excess
We extend the standard model to include a weak-triplet and color-octet
scalar. This `octo-triplet' field consists of three particles, two charged and
one neutral, whose masses and renormalizable interactions depend only on two
new parameters. The charged octo-triplet decay into a W boson and a gluon is
suppressed by a loop factor and an accidental cancellation. Thus, the main
decays of the charged octo-triplet may occur through higher-dimensional
operators, mediated by a heavy vectorlike fermion, into quark pairs. For an
octo-triplet mass below the t\bar{b} threshold, the decay into Wb\bar{b} or
Wb\bar{s} through an off-shell top quark has a width comparable to that into
c\bar{s} or c\bar{b}. Pair production with one octo-triplet decaying into two
jets and the other decaying into a W and two soft b jets may explain the
dijet-plus-W excess reported by the CDF Collaboration. Using a few kinematic
distributions, we compare two mechanisms of octo-triplet pair production:
through an s-channel coloron and through the coupling to gluons. The
higher-dimensional operators that allow dijet decays also lead to CP violation
in B_s - \bar B_s mixing.Comment: 18 pages. New CDF kinematic distributions using 7.3 fb^{-1} compared
to both resonant and gluon-induced pair production of octets. Corrections in
Section 3.1. Comment on the D0 Wjj result included in Section 3.3.
Implications for LHC expanded in Section 3.
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