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161.
162.
D. Sohler Zs. Dombrádi S. Brant J. Cederkäll M. Lipoglavšek M. Palacz V. Paar J. Persson A. Atac̣ C. Fahlander H. Grawe A. Johnson A. Kerek W. Klamra J. Kownacki A. Likar L. O. Norlin J. Nyberg R. Schubart D. Seweryniak G. de Angelis P. Bednarczyk D. Foltescu M. Fayez-Hassan D. Jerrestam S. Juutinen E. Mäkelä B. M. Nyakó M. de Poli H. A. Roth T. Shizuma Ö. Skeppstedt G. Sletten S. Törmänen 《Zeitschrift für Physik A Hadrons and Nuclei》1997,357(3):239-240
Excited states of 65Ge were populated via the 12C + 58Ni (261 MeV) reaction using the NORDBALL detector array equipped with charged-particle and neutron detector systems for reaction channel separation. On the basis of γγ-coincidence relations and angular distribution ratios a significantly extended level scheme was constructed up to E x = 9 MeV and J π = (33/2?). The low-energy states of the nucleus are discussed in the framework of the interacting boson-fermion model. 相似文献
163.
The model estimates, subject to restrictions, the functional relationship between national sulfur dioxide discharges and investment in control technology development. Estimates may be made for different product demands, allowed cost increases, and clean fuel availabilities. Control technology development may be accelerated by increased investment. Both optimal and sub-optimal solutions are calculated for an example problem. A general computing method is provided.The model was presented at the Industrial Process Design for Pollution Control Workshop, Chicago, Illinois, Oct. 1973; copyright released by the American Institute of Chemical Engineers for publication for the first time in the monographNormative Analysis in Policy Decisions: Public and Private. 相似文献
164.
Johnson Charles R.; Lundquist Michael; Naedal Geir 《Journal London Mathematical Society》1999,59(2):507-520
The problem of completing a partially prescribed Toeplitz matrixto a positive definite Toeplitz matrix is considered. The mainresult is a characterization of the patterns of specified entriesthat guarantee the existence of a positive definite Toeplitzcompletion of a partial positive definite Toeplitz matrix. Thischaracterization resolves affirmatively a conjecture of C. R.Johnson and L. Rodman. 相似文献
165.
S. Bates W. B. Johnson J. Lindenstrauss D. Preiss G. Schechtman 《Geometric And Functional Analysis》1999,9(6):1092-1127
New concepts related to approximating a Lipschitz function between Banach spaces by affine functions are introduced. Results
which clarify when such approximations are possible are proved and in some cases a complete characterization of the spaces
X, Y for which any Lipschitz function from X to Y can be so approximated is obtained. This is applied to the study of Lipschitz and uniform quotient mappings between Banach
spaces. It is proved, in particular, that any Banach space which is a uniform quotient of L
p
, 1 < p < , is already isomorphic to a linear quotient of L
p
.
Submitted: June 1998, revised: December 1998. 相似文献
166.
167.
Input data modeling is a critical component of a successful simulation application. A perspective of the area is given with an emphasis on available probability distributions as models, estimation methods, model selection and discrimination, and goodness of fit. Three specific distribution classes (lambda,S
B
, TES processes) are discussed in some detail to illustrate characteristics that favor input models. Regarding estimation, we argue for maximum likelihood estimation over method of moments and other matching schemes due to intrinsic superior properties (presuming a specific model) and the capability of accommodating messy data types. We conclude with a list of specific research problems and areas warranting additional attention. 相似文献
168.
A selected bibliography on degeneracy problems organized according to the appearance of the respective references in various fields of operations research is given. 相似文献
169.
This is the second edition of a quarterly column the purpose of which is to provide a continuing update to the list of problems (NP-complete and harder) presented by M. R. Garey and myself in our book “Computers and Intractability: A Guide to the Theory of NP-Completeness,” W. H. Freeman & Co., San Francisco 1979 (hereinafter referred to as “[G&J]”; previous columns will be referred to by their dates). A background equivalent to that provided by [G&J] is assumed. Readers having results they would like mentioned (NP-hardness, PSPACE-hardness, polynomial-time-solvability, etc.), or open problems they would like publicized, should send them to David S. Johnson, Room 2C-355, Bell Laboratories, Murray Hill, NJ 07974, including details, or at least sketches, of any new proofs (full papers are preferred). In the case of unpublished results, please state explicitly that you would like the results mentioned in the column. Comments and corrections are also welcome. For more details on the nature of the column and the form of desired submissions, see the December 1981 issue of this journal. 相似文献
170.
Translation planes of order q
2 containing non-Desarguesian Baer subplanes are used to construct transversal-free translation nets with very small deficiencies. Also, a generalization of the ideas of Bruen shows that any non-Desarguesian spread in PG(3, q) produces a transversal-free net of small deficiency. 相似文献