Objectives: The purpose of this study is to analyze a strategy for the assignment and transportation of injured patients to hospital to decrease the demand on transportation, in both predisaster and postdisaster periods, on the Anatolian side of Istanbul. Methods: Two approaches are used in this study: a Voronoi diagram, and a heuristic approach to the problem of scheduling. A Voronoi diagram is used to divide the city into 74 regions, where each hospital has a certain region of responsibility. The transportation strategy of 1 hospital is modeled by minimizing the makespan (ie, the maximal completion time) and the work-in-process, which are used as different objectives in scheduling theory. Results: The total waiting time of 100 injured people was minimized to 13,036 min when a total of 3 vehicles was used in the studied region, on the Asian side of Istanbul. The transportation capacity and total operating capacity of the hospitals should be approximately equal. Conclusions: The people of Istanbul will be in a safer position if the suggested measures are implemented. This is an important consideration, as Istanbul is situated in a region where serious earthquakes are possible at any moment.

The countries are the units that procure the vaccines during the COVID-19 pandemic. The delivered quantities are huge. The countries must bear the inventory holding cost according to the variation of stock quantities. This cost depends on the speed of the vaccination in the country. This speed is time-dependent. The vaccinated portion of the population can be approximated by the cumulative distribution function of the Cauchy distribution. A model is provided for determining the minimal-cost inventory policy and its optimality conditions are provided. The model is solved for 20 countries for different numbers of procurements. The results reveal the individual behavior of each country.

The aim of this study is the determination of optimum process parameters which will provide the finest and the most uniform electrospun Polyvinylpyrrolidone (PVP) based nanofibers with Taguchi experimental design. For the designed experimental setup, parameters (solvent type, polymer concentration, voltage, distance between the electrodes, solution feed rate and humidity) were used which effect the electospinning process significantly. For this purpose, the appropriate orthogonal array was selected to determine the factors and levels at Taguchi experimental design application. The experimental design aimed which provides to be reduced the number of experiments and minimised the effect of uncontrollable factors with less experiments to obtain target value by using Taguchi orthogonal arrays. In the experimental studies of paper, firstly PVP polymer solutions such as conductivity, surface tension and viscosity were determined with various PVP concentrations (10, 12, 14 wt %) and solvents (ethanol, dimethylformamide, dimethylacetamide, chloroform, acetic acid and distilled water). Scanning Electron Microscope (SEM) images of electrospun PVP based nanofibrous surfaces were obtained, average fiber diameter and fiber diameter coefficient values were calculated by ImageJ image analyses software and fiber diameter distribution histogram curves were obtained by SPSS program. Experimental results were analyzed and commented by Taguchi method in MINITAB program with variance analysis. According to the results; solvent type has the highest effect on the electrospinning of PVP nanofibers. In this study, it is predicted to save in terms of time and cost with decreasing the number of experiments by Taguchi experiment design.