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961.
LetK be an algebraically closed field withp:=char (K)>0 andX a bielliptic curve over Spec(K) with genus≥6 and such that the canonical model ofX is ordinary. In this paper we determine all the possible gap sequences of Weierstrass points on such curves. 相似文献
962.
Gur Mosheiov 《The Journal of the Operational Research Society》1996,47(9):1184-1191
We study a problem of scheduling deteriorating jobs, i.e. jobs whose processing times are an increasing function of their starting times. We consider the case of a single machine and linear job-independent deterioration. The objective is to minimize the sum of weighted completion times, with weights proportional to the basic processing times. The optimal schedule is shown to be Λ-shaped, i.e. the sequence of the basic processing times has a single local maximum. Moreover, we show that the problem is solved in O(N log N) time. In the last section we test heuristics for the case of general weights. 相似文献
963.
Anhydrites(II)- CaSO4 were prepared from two waste gypsums (PRECHEZA Perov, FOSFA Potorná). The samples of anhydrites(II) with sulphate activators were tested on spillage, beginning and the end of setting time, bending and pressure strength. Both sodium and potassium sulphates accelerated setting of anhydrite, more impressively that prepared from Potorná gypsum. The addition of Na2SO4 influenced the strength of this anhydrite very favourably. On the contrary K2SO4 influenced favourably the strength of Perov anhydrite. Results confirm the necessity to evaluate properties of such materials with respect to their origin. 相似文献
964.
Gerhard Hasslinger Erik S. Rieger 《The Journal of the Operational Research Society》1996,47(5):640-653
This paper deals with approximate analysis methods for open queueing networks. External and internal flows from and to the nodes are characterized by renewal processes with discrete time distributions of their interarrival times. Stationary distributions of the waiting time, the queue size and the interdeparture times are obtained using efficient discrete time algorithms for single server (GI/G/1) and multi-server (GI/D/c) nodes with deterministic service. The network analysis is extended to semi-Markovian representations of each flow among the nodes, which include parameters of the autocorrelation function. 相似文献
965.
Steve PhillipsJr. 《The Journal of the Operational Research Society》1996,47(5):697-701
The paper presents an application oriented procedure for solving the project management duration/resource tradeoff problem. A procedure is presented for reducing a project from a normal to a crash duration state at a minimum amount of additional resource expenditure assuming a linear utilization functions. The procedure is network based using a graphical Cut Search Approach to locate the minimal resource level at each reduction in total project duration. Activity-on-arc networks and flow networks are utilized. The paper is presented for practical application and for conceptual development as compared to a theoretical treatment. 相似文献
966.
Krishna S Kumar 《Pramana》1993,41(1):45-53
We report on two sensitive tests of lepton universality carried out by the 4 LEP experiments at the Z0 pole. From measurements of the τ polarization in e+ e?→τ + τ ?, the ratios of the vector and axial vector coupling constants of the electron and the tau lepton to the weak neutral current are obtained to beg v e /g a e =0.066±0.015 andg V τ /g A τ =0.070±0.009 respectively. From measurement of the τ lifetime and the τ leptonic branching ratios, the ratio of the coupling constants describing weak leptonic decays of the τ and the μ is measured to beG τ /G μ =0.996±0.008. 相似文献
967.
A review is given of the StandardSU(5) supergravity model. This model has passed an important check regarding unification of the electro-weak and the strong couplings using high precision LEP data. It is shown that for a significant domain of the parameter space the model also satisfies constraints on the SUSY spectrum from CDF and LEP, as well as proton stability and cosmological relic density constraints. 相似文献
968.
Based on thermodynamic analysis of interfacial segregation, the segregation enthalpy H
o of a solute I in a given matrix was found to depend linearly on two mutually independent terms reflecting the type of interface and the solid solubility limit X
infI
sup*
at temperature T and can be written as In this equation, the structural dependence of interfacial segregation is contained in H
*() which corresponds to the extrapolated segregation enthalpy of a solute with unlimited solubility in the matrix. The product [Tln(X
infI
sup*
)] is essentially constant with temperature, and can therefore be obtained from data for maximum solid solubility, [Tln(X
infI
sup*
)]max. The parameter v>0 represents the relationship between the activity a
infI
sup*
of a solute at the bulk solid solubility limit in a given matrix and X
infI
sup*
, a
infI
sup*
=(X
infI
sup*
)
v
, and is characteristic for the matrix. Using recent experimental data for silicon, phosphorus, and carbon segregation at well-characterized grain boundaries in oriented bicrystals of -iron, the averaged value
was determined. Values of H
*() range from -8 kJ/mol (general grain boundaries) up to +8 kJ/mol (special grain boundaries). These values are discussed and used for a more precise and generalized construction of grain boundary segregation diagrams of -iron. 相似文献
969.
The problem of calculation of Sturmian functions (positive energy Weinberg states) for nonlocal (exchange) interactions is considered. It is shown that the method of continued fractions proposed by Horáek and Sasakawa makes the calculation of Sturmian eigenfunctions and eigenvalues feasible even for complicated nonlocal interactions. As an example Sturmian functions and Sturmian eigenvalues for the low energy electron-hydrogen scattering in the static exchange approximation are calculated. In addition a very general proof of convergence of the method of continued fractions is presented.Dedicated to the memory of Professor Jozef Kvasnica. 相似文献
970.
Frabetti PL Cheung HW Cumalat JP Dallapiccola C Ginkel JF Greene SV Johns WE Nehring MS Butler JN Cihangir S Gaines I Garren L Garbincius PH Gourlay SA Harding DJ Kasper P Kreymer A Lebrun P Shukla S Bianco S Fabbri FL Sarwar S Zallo A Culbertson R Gardner RW Greene R Wiss J Alimonti G Bellini G Caccianiga B Cinquini L Di Corato M Giammarchi M Inzani P Leveraro F Malvezzi S Menasce D Meroni E Moroni L Pedrini D Perasso L Sala A Sala S Toretta D Vittone M Buchholz D Claes D Gobbi B O'Reilly B 《Physical review letters》1993,70(12):1755-1758