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171.
Data from a neutrino and antineutrino hydrogen experiment with BEBC are used to investigate transverse properties of the produced charged hadrons. Measurements are presented on average transverse momenta of charged pions as functions of Feynman-x and the hadronic mass, on the transverse momentum flow within an event and on jet-related quantities. The main features of the data are well described by the LUND model. The data favour a version of the model in which soft gluon effects are included and the primordial transverse momentum of the quarks in the proton is small. Effects from 1st order QCD (hard gluon emission) are negligible.  相似文献   
172.
A latin square of order ten is displayed having an orthogonal mate, but no nontrivial automorphism obtainable by permutation of rows, columns and digits.  相似文献   
173.
Barium, lanthanum and cerium were determined by excitation using a 100 mCi241Am radioisotope source with the utilization of the K peaks. This work forms part of the UNESCO Project IGGP-129. This work includes data from the MS Thesis of D. ADAMES.  相似文献   
174.
In this paper we demonstrate the use of picosecond time-resolved infrared spectroscopy (ps-TRIR) to monitor the early structural dynamics of DNA bases and polydeoxynucleotides following UV excitation in solution.  相似文献   
175.
We give symmetric presentations for groups closely related to the three sporadic Fischer groups Fi22, Fi23 and Fi24.Mathematics Subject Classiffications (2000). 20D08, 20D06, 20F05This research was supported by an EPSRC grant ref. GR/N27491/01  相似文献   
176.
Four linearly independent linear combinations of the ten sextic centrifugal distortion coefficients of triangular triatomic molecules are presented. These combinations are formed in such a way that the resulting expressions depend only on the equilibrium geometry and the harmonic force field parameters of the molecule, quantities which are ordinarily known to considerably better precision than the sextic constants. The relations obtained thus constitute a set of planarity constraints on the ten sextic coefficients which arise in connection with the Nielsen-Amat expansion of the Darling-Dennison Hamiltonian. The planarity expressions can be utilized to effect a reduction of the sextic portion of the Hamiltonian.  相似文献   
177.
Recent attempts at consumer participation in the health care planning process have proved weak in their ability to responsively account for consumer health welfare. This can be attributed, in large part, to the mechanisms employed for identifying and utilizing the consumer's health care views and preferences. A heuristic planning procedure designed to overcome these problems by directly incorporating consumer preferences is developed. It identifies that (primary) health care delivery system which maximizes total incremental health benefit to a community subject to a prespecified budget constraint. The model assumes a methodology (previously developed by the author) for measuring, in aggregable units, the benefit, Bip, from some health care facility p as perceived by some consumer i. Application of the procedure and subsequent sensitivity analyses demonstrate its ability to generate valid solutions that are robust to disturbances in the planning system.  相似文献   
178.
179.
Theoretical expressions for surface displacements accompanying the propagation of acoustic waves in a buried gas-filled pipe are derived. It is shown that the radiated field consists of both shear and compressional components of comparable amplitude which interfere with one another because of the large difference in the respective propagation velocites. This is manifested at the surface by a series of maxima and minima in the vertical and horizontal displacements. Comparing the theoretical calculation to experimental data on vertical surface displacements generated by plane progressive waves at frequencies ranging from 200 to 2000 Hz within an underground pipe shows that only axisymmetric radial and longitudinal vibration of the pipe wall is important. This stands in marked constant to experiments carried out by others in an air medium in which the contribution of bending mode excitation was shown to be significant, particularly at lower frequencies. The theory can be fitted to the experimental data only if the compressional and shear velocities α and β, respectively, are narrowly specified, leading to α = 259 m/s and β = 164 m/s, the latter being in reasonable agreement with the results of other investigators for clay soil.  相似文献   
180.
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