149 resultados para Hard combinatorial scheduling
Resumo:
Strict next-to-leading order (NLO) results for the dilepton production rate from a QCD plasma at temperatures above a few hundred MeV suffer from a breakdown of the loop expansion in the regime of soft invariant masses M 2 ≪ (πT)2. In this regime an LPM resummation is needed for obtaining the correct leading-order result. We show how to construct an interpolation between the hard NLO and the leading-order LPM expression, which is theoretically consistent in both regimes and free from double counting. The final numerical results are presented in a tabulated form, suitable for insertion into hydrodynamical codes.
Resumo:
The aim of this study was to compare the speech in subjects with cleft lip and palate, in whom three methods of the hard palate closure were used. One hundred and thirty-seven children (96 boys, 41 girls; mean age = 12 years, SD = 1·2) with complete unilateral cleft lip and palate (CUCLP) operated by a single surgeon with a one-stage method were evaluated. The management of the cleft lip and soft palate was comparable in all subjects; for hard palate repair, three different methods were used: bilateral von Langenbeck closure (b-vL group, n = 39), unilateral von Langenbeck closure (u-vL group, n = 56) and vomerplasty (v-p group, n = 42). Speech was assessed: (i) perceptually for the presence of a) hypernasality, b) compensatory articulations (CAs), c) audible nasal air emissions (ANE) and d) speech intelligibility; (ii) for the presence of compensatory facial grimacing, (iii) with clinical intra-oral evaluation and (iv) with videonasendoscopy. A total rate of hypernasality requiring pharyngoplasty was 5·1%; total incidence post-oral compensatory articulations (CAs) was 2·2%. The overall speech intelligibility was good in 84·7% of cases. Oronasal fistulas (ONFs) occurred in 15·7% b-vL subjects, 7·1% u-vL subjects and 50% v-p subjects (P < 0·001). No statistically significant intergroup differences for hypernasality, CAs and intelligibility were found (P > 0·1). In conclusion, the speech after early one-stage repair of CUCLP was satisfactory. The method of hard palate repair affected the incidence of ONFs, which, however, caused relatively mild and inconsistent speech errors.
Resumo:
In this paper, we are concerned about the short-term scheduling of industrial make-and-pack production processes. The planning problem consists in minimizing the production makespan while meeting given end-product demands. Sequence-dependent changeover times, multi-purpose storage units with finite capacities, quarantine times, batch splitting, partial equipment connectivity, material transfer times, and a large number of operations contribute to the complexity of the problem. Known MILP formulations cover all technological constraints of such production processes, but only small problem instances can be solved in reasonable CPU times. In this paper, we develop a heuristic in order to tackle large instances. Under this heuristic, groups of batches are scheduled iteratively using a novel MILP formulation; the assignment of the batches to the groups and the scheduling sequence of the groups are determined using a priority rule. We demonstrate the applicability by means of a real-world production process.
Resumo:
This paper deals with an event-bus tour booked by Bollywood film fans. During the tour, the participants visit selected locations of famous Bollywood films at various sites in Switzerland. Moreover, the tour includes stops for lunch and shopping. Each day, up to five buses operate the tour; for organizational reasons, two or more buses cannot stay at the same location simultaneously. The planning problem is how to compute a feasible schedule for each bus such that the total waiting time (primary objective) and the total travel time (secondary objective) are minimized. We formulate this problem as a mixed-integer linear program, and we report on computational results obtained with the Gurobi solver.