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The problem of sizing the resources of a production system is widely encountered both in the literature and in practice. Simulation is a very useful method to identify the necessary number of resources. However, if there are numerous resources, it can become impossible to make a sound 'trial-and-error' analysis with simulation models, so that strategies using simulation optimization appear as an attractive approach. Unfortunately, it is necessary to specify a cost function, and, in practice, it is often very difficult to formalize such a function which is used to determine the number of resources that will minimize this cost. In this article, we propose a different modelling approach, which aims at sizing the resources so as to meet the design specifications. In this respect, we search for the minimum number of resources of each type, while satisfying the performance requirements specified in the design project. As a result, the problem is formulated as a stochastic multi-objective optimization problem with constraints. The approach used here is based on simulation, used in conjunction with a bootstrap approach which accounts for the stochastic aspect of the model, and with regression metamodelling in order to derive an analytical formulation of the constraints together. Different multi-objective optimization methods can then be used to solve the problem. An illustrative example is given. [ABSTRACT FROM AUTHOR]

Running biomechanics and its evolution that occurs over intensive trials are widely studied, but few studies have focused on the reproducibility of stride evolution in these runs. The purpose of this investigation was to assess the reproducibility of changes in eight biomechanical variables during exhaustive runs, using three-dimensional analysis. Ten male athletes (age: 23 ± 4 years; maximal oxygen uptake: 57.5 ± 4.4 ml0 2 ·min -1 ·kg -1 ; maximal aerobic speed: 19.3 ± 0.8 km·h -1 ) performed a maximal treadmill test. Between 3 to 10 days later, they started a series of three time-to-exhaustion trials at 90% of the individual maximal aerobic speed, seven days apart. During these trials eight biomechanical variables were recorded over a 20-s period every 4 min until exhaustion. The evolution of a variable over a trial was represented as the slope of the linear regression of these variables over time. Reproducibility was assessed with intraclass correlation coefficients and variability was quantified as standard error of measurement. Changes in five variables (swing duration, stride frequency, step length, centre of gravity vertical and lateral amplitude) showed moderate to good reproducibility (0.48 ≤ ICC ≤ 0.72), while changes in stance duration, reactivity and foot orientation showed poor reproducibility (-0.71 ≤ ICC ≤ 0.04). Fatigue-induced changes in stride biomechanics do not follow a reproducible course across the board; however, several variables do show satisfactory stability: swing duration, stride frequency, step length and centre of gravity shift.

Background: Various clinical trials have demonstrated the benefits of physical training offered during and/or after breast cancer treatments. However, given the variety of adverse events that may be encountered, physical training could be combined with psychologic, relational, and social guidance. This kind of multidisciplinary program, as well as its long-term effects, have been little studied so far. Therefore, the objective of our study was to determine the benefits at 3, 6, 12, and 24 months of a 3-month exercise and education program among women after breast cancer treatment., Patients and Methods: Two hundred nine outpatients treated for primary breast carcinoma were divided into a control group (n = 106) and an experimental group (n = 103) which underwent a 3-month rehabilitation program including physical training and psychoeducational sessions. The assessments, performed before the program and at 3, 6, 12, and 24 months after inclusion, included validated questionnaires on quality of life and symptoms., Results: The analyses revealed an improvement in quality of life and symptoms after the exercise and education program within the experimental group and a maintenance of these improvements during the 2 years of follow-up. These improvements were significantly better than those in the control group, clearly demonstrating that the program has benefits., Conclusion: This trial identified the benefits of a well-detailed 3-month exercise and education program over 24 months' follow-up among women after breast cancer treatment., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Background: Different clinical trials show beneficial effects of physical training offered during and/or after breast cancer treatment. However, given the variety of side effects that may be encountered, physical training could be combined with psychological, relational and social guidance. This kind of multidisciplinary program has been little studied so far., Aim: The aim of this study was to determine the benefits of a three-month multidisciplinary rehabilitation program among women after breast cancer treatment., Design: Controlled no-randomized trial., Setting: University for outcomes, University Hospital Center for interventions., Population: Two hundred and nine outpatients who have been treated for a primary breast carcinoma., Methods: Patients were divided into a control group (N.=106) and an experimental group (N.=103) which has benefited from a rehabilitation program of three months including physical training and psycho-educational sessions. The assessments, performed before and after the program, included functional assessments ("Sit and Reach Test", maximal incremental exercise test and "Six-Minute Walk Test"), body composition measurements (Body Mass Index [BMI] and body fat percentage) and a questionnaire (European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Core 30)., Results: After three months, flexibility, walking distance and all parameters measured during the maximal incremental exercise, except maximal heart rate, were significantly improved in the experimental group. The body fat percentage was significantly decreased and a significant improvement was observed for perceived health status (quality of life), functional role, emotional state, physical, cognitive and social functions and for most symptoms. In the control group, most of these improvements didn't appear and a significant increase in BMI and body fat percentage was observed., Conclusions: This trial identifies the benefits of a well detailed multidisciplinary rehabilitation program, including physical re-conditioning and psycho-educational sessions, with important improvements in functional capacity, body composition and the majority of functions and symptoms among women after breast cancer treatment., Clinical Rehabilitation Impact: Through its results, this study could contribute to the development of hospital quality standards for oncologic rehabilitation. Physiotherapists can efficiently propose this kind of multidisciplinary rehabilitation program.

The authors report a prospective study concerning 90 children with a urinary tract infection, investigated for the first time by radiological and ultrasonographic techniques. Amongst these 90 children, 50 (i.e. 55% of cases) had a normal retrograde cystography and ultrasonography. These children did not have any IVU and medical surveillance proved to be sufficient. Ten patients had a normal retrograde cystography and abnormal ultrasonography. Intravenous urography carried out in these 10 cases revealed in 8 instances an abnormality of the upper urinary tract. Finally 30 children had an abnormal retrograde cystography, with reflux in 29 cases, leading to intravenous urography which yielded a pathological result in only half of the cases studied. This series confirms the central role of retrograde cystography. When it is normal, intravenous urography may be legitimately substituted by ultrasonography.