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Aiming at the problem that the uncertain disturbance factors in the workshop production have an impact on the real-time execution of the scheduling scheme, a job shop scheduling scheme with place buffer under uncertain disturbance was proposed to deal with the disturbance factors in the production workshop system combining simulation technology with intelligent optimization algorithm. Normally distributed random variables were utilized to describe uncertain processing time, and uniformly distributed intervals were employed to describe the average failure interval time and average repair time. The place buffer's parameters before severely blocked equipment were adjusted to affect the maximum completion time. An uncertain scheduling simulation model for job shop production was constructed by Plant Simulation software and genetic algorithm was used to solve the model. The simulation results showed that the adjustment of the place buffer's time parameter could obtain the best fitness value, which verified that the proposed method could effectively reduce the impact caused by uncertain processing time and random machine failures during the workshop production scheduling. [ABSTRACT FROM AUTHOR]

Objective: To summarize the disposal methods and the reasons of complications in operation of totally implantable central venous port (TICVP)., Methods: A total of 2 007 patients were enrolled in this observational, single-center study between December 2008 and March 2013. TICVP implantation was performed with one small skin incision and subcutaneous puncture of subclavian or jugular vein. Patient's profiles, indications of port system, early and delayed complications, and disposal methods were evaluated. There were 38 male and 1 969 female patients, aged from 21 to 85 years, with a mean of 47.6 years., Results: The mean duration of the TICVP system was (242 ± 12) days, ranging from 9 to 1 243 days. The achievement rate of puncture in the right jugular vein (99.76%) was the highest. Sonographic approach using the internal jugular vein were better than the external landmark-guided technique (99.80% vs. 96.34%, χ² = 29.905, P = 0.000). The rate of immediate complication was 0.80%, which included pneumothorax, hemothorax, lymphatic fistula and thrombosis. Early complications rate was 0.10%, which included pocket hematoma, catheter migration, venous thrombosis, port pocket infection, fibrin sheath formation. Late complications rate was 7.87%, which included catheter fracture, pinch-off syndrome, catheter-related bloodstream infection, fibrin sheath formation, catheter migration, extravasation, port inversion and port reveal. The rate of removal due to complications was 1.34% (27/2 007), and the early complication was higher (χ² = 8.053, P = 0.011)., Conclusions: The low incidence of complications suggests that TICVP is safe and reliable for long term intermittent venous access. The results support the use of TICVP in the oncology patients and patients requiring long-term intravenous therapy.