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In this paper, we study the medical team planning and scheduling in home healthcare within a weekly horizon, including the planning of nursing visits and the daily traveling route scheduling. Two objectives are considered: the first one is to minimize the total operation cost of the healthcare agency and the second one is to maximize the patient satisfaction. The problem is formulated as a mixed integer program, to seek for a trade-off between two objectives, with the characteristics of the patient requirements including nursing types, nursing frequency and service length considered. Medical team types, available service days and overwork penalty are also respected in the model. Then an $$\epsilon $$ -constraint method is adopted to obtain exact non-dominated solutions. To address large-scale problem instances, three heuristic approaches are developed to generate approximate Pareto fronts in a reasonable time. The set of non-dominated solutions are valuable for decision-making. Computational experiments are conducted and the results demonstrate the efficiency of the approaches.

The differences in planetary boundary layer characteristics, in particular atmospheric boundary layer height (ABLH), humidity, and local circulations in pre-monsoon and monsoon period over the Erhai Lake, were simulated by the lake-atmosphere coupled model WRF v3.7.1. No lake simulations were also conducted to investigate lake effects over complex topography. During pre-monsoon period, local circulation was fully developed under weak synoptic system. The ABLH ran up to 2300 m or so. During monsoon period, temperature difference between land and lake became smaller, resulting in weaker local circulations. The height of circulation reduced by 500 m, and ABLH ran up to 1100 m during the day. Enhanced soil moisture and low surface temperature due to monsoon rainfalls in July could be the main reason for the slightly lower ABLH over the Erhai Lake area. Specific humidity of the boundary layer increased 8.8 g kg−1 or so during monsoon period. The Erhai Lake enlarged thermal contrast between valley and mountain slope in the Dali Basin. The lake reduced air temperature by 2~3 °C during daytime and increased air temperature by nearly 2 °C in the evening. Due to its small roughness length and large thermal capacity, the Erhai Lake enlarged lake-land temperature difference and local wind speed. A cyclonic circulation was maintained by the combination of mountain breeze and land breeze in the south of the lake. The lake decreased air temperature, increased specific humidity, and reduced ABLH during daytime, whereas the opposite effect is presented at night.

This paper investigates quay crane scheduling problem at container ports, subject to arbitrary precedence constraint. Differing from traditional machine scheduling problems, non-crossing constraint must be satisfied because parallel quay cranes mount on a same rail to unload or load containers. Precedence relation in an arbitrary form is rarely investigated in the literature, however it may be originated from (i) reefers or dangerous cargo which requires high priority of processing, and (ii) yard stacking plan. We present computational complexity for several problem variations. We show the problem, even without precedence constraint, is strongly NP-hard, which improves the state-of-the-art. A genetic algorithm is proposed to obtain near-optimal solutions. Computational experiments demonstrate the efficiency.

International audience; We study a deterministic storage yard management problem which jointly determines storage space allocation and yard crane assignment. The problem is first formulated as an integer grogram to minimize the total operational cost. To solve large-scaled problems, we then transform it to a set partitioning formulation and provide a framework of branch-and-price algorithm. Computational experiments to explain the performance of the solution approach are to be further conducted.

Evaluation of the WRF3.7.1 lake model performance on lake physical processes and lake-atmosphere interaction at Erhai Lake was conducted with in-situ observation data sets over the lake to verify the model results. The lake model with default parameters presented significant negative bias during the day and positive bias during the night on lake surface temperature. Calibrations of water absorption and extinction coefficients, surface roughness length and eddy diffusion coefficient were carried out to correct this bias. The added absorption and extinction coefficients increased solar radiation in upper water layer, leading to a little higher surface temperature. Compared to constant surface roughness lengths, parameterization of roughness lengths as functions of friction velocity and fetch length significantly improved simulations of lake surface temperature and sensible heat flux. In Erhai Lake, eddy diffusion coefficient of the Henderson-Sellers parameterization is smaller than that in deep lakes. The eddy diffusion coefficient was reduced by a factor of 0.05 in dry season and 0.02 in wet season respectively to restrict mixing strength, generating a reasonable diurnal range with observed surface temperature. The adjusted parameters simulations matched better with in-situ observations in diurnal cycle of temperature and surface heat fluxes, but still overestimated wind speed. Topographic correction is effective to correct the bias, indicating topographic correction over complex terrain was necessary.