Lamb’s problem

Now the field due to a delta function source Qz = S(z — zo)5(x) is known as Lamb s problem, and at some distance from x = 0 the solution is known (Achenbach 1973). If the surface displacement of the surface wave generated by the concentrated load is wz x, C) and the depth of the crack is d, then for the distributed body forces, by superposition,... 

In elastodynamics as well as in seismology, the problem where a force is applied in a half space is called Lamb s problem. This is because the problem was first solved by Lamb [1904]. Then, Pekeris published famous results of Lamb s solutions due to a surface pulse (Pekeris 1955) and a buried pulse (Pekeris 1955). 

Fig. 7.12. Source-time functions df(t)/dt by deconvolution analysis of Lamb s problem due to a surface pulse. The solid curve is analyzed and the broken is assumed in the synthesized waveform.

Breckenridge FR, Tschiegg CE, Greenspan M (1975) Acoustic Emission Some Applications of Lamb s Problem. J Acoust Soc Am 57 626-631... 

Johnson LR (1974) Green s Function for Lamb s Problem. Geopys JR astr Soc, 37 99-131... 

Robert focused on two problems extension of Einstein s theory to higher concentrations and then to nonspherical particles. Armed with the tools provided by Lamb s hydrodynamic bible, Einstein s famous doctoral dissertation and a lengthy review by Guth and Mark, I started out. After an unsatisfactory beginning and a Black Sea vacation [Simha, 1999], he successfully extended the treatment of viscosity, t], to higher concentrations by including binary hydrodynamic interactions ... 

Lamb and calf heart, lamb brain and different molluscs have been examined, as intact tissues or as homogenates. A 33S taurine spectrum in vivo has been obtained from L. lithophaga, due to its cylindrical shape, in about 8 min with a 10 mm probe (S/N = 3). Particularly important is the possibility of performing a quantitative determination of the taurine content. In this case, the major problem is to measure the intensity of the signals with good accuracy. 

An interesting problem is the precise calculation and measurement of the Lamb shift 6 which we describe here, commenting on the main points of interest. First, there is a disparity - not yet accounted for - both between the at present most precisely known theoretical values of S, as well as between experiment and theory. Another important point is the opportunity provided to obtain information on the structure and properties of corrections which are not given directly by QED. In contrast to the anomalous magnetic moment, the Lamb shift characterizes the properties of bound electrons, i.e. it takes account of not only the QED effects but the effects arising from the nuclear structure. If the corrections independent of QED are far beyond the error limits of measurements for an anomalous magnetic moment, the corrections... 

The paper that reported these results ended with the recognition that there was a problem Whether the failure of theory and experiment to agree is because of some unknown factor in the theory of the hydrogen atom or simply an error in the estimate of one of the natural constants, such as [the fine structure constant], only further experiment can decide. This was the result that Rabi conveyed to the physicists at Shelter Island. Rabi s reputation as an experimentalist brought credibility to the measured results and issued a challenge to the theorists. As with the Lamb shift, it was quantum electrodynamics that was brought to bear on... 

The confirmation by Lamb and Retherford of the inadequacy of the Dirac theory stimulated a re-examination of a theoretical problem to which only a very incomplete solution had so far been found the problem of the interaction between charged particles and the electromagnetic field. We shall briefly refer to the problem as it presented itself in classical physics, and then (following Weisskopf [135]) notice the further difficulties which the quantum theory introduces. Finally we shall see how these difficulties have been circumvented by the new quantum electrodynamics, and how a small correction is thereby introduced to the energy levels predicted by Dirac s theory. The new theory, however, is not a complete and logically satisfactory solution to the problems we shall state a difficulty of principle remains now, as formerly. 

Hardwoods have been preferred for intensive plantation management because of their sprouting capability and the fast growth of these sprouts for the first 10-20 years, as compared to conifers.There are exceptions, however, where conifers may be more desirable. Williford et al. (2Q) reported loblolly pine (Pinus taeda L.) to be superior in biomass production on many sites in the south. Studies by the U.S. Forest Service at Rhinelander, Wisconsin, indicate conifers may have advantages under certain site conditions ( ). For example, jack pine (Pinus banksiana Lamb.) is well adapted to the North, has few serious insect and disease problems, and is less demanding of nutrients and moisture than many hardwoods. 

PP, Box 168, American Chemical Society Correspondence 1925-1944, Letter from Pauling to Lamb, February 11, 1931. In AHQP, in the interview with Pauling, Pauling referred to the frequent delays in publication in the JACS, but especially to the problems he previously experienced with editor and referees, for his were largely theoretical papers. In 1929, Pauling published a paper on "The Principles Determining the Stmcture of Complex Ionic Crystals," which he had to reduce to half to comply with the editor s request. 

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