Scheduling flexibility

Although project management was certainly applied in practice prior to the mid-1950 s, the development of the critical path method and the Project Evaluation and Review Technique (PERT) is considered to be the initiation of the modern practice of project management. The critical path method is a network analysis technique used to predict project duration by analyzing which sequence of activities or path most likely has the least amount of scheduling flexibility or... 

Advantages of nonprogressive 1. Balance delay 2. Scheduling flexibility 3. Shocks 4. Cumulative trauma 5. Satisfaction No balance delay. Can make multiple products at same time. Do not affect multiple stations. Less CT since greater variety in motions. Each worker does complete job. 

Accelerated drying for smaller kiln charges. The ability to dry at the same time different species and dimensions allows for greater production and scheduling flexibility. The RFV kilns can also be used for pasteurization and fixation of preservatives. 

For shippers and transportation providers, an important metric is the total supply chain cost of transportation transactions. This total supply chain cost includes the effect on both transport costs and associated inventory costs. In addition, measures of performance include delivery lead time, percent on-time delivery or delivery within time windows, and schedule flexibility to accommodate shipment reschedules. Given the large volume of shipments that occur on dedicated contract trucking, there is scope for use of information, coordination agreements, and associated capadty commitments to improve performance across a supply chain. Competing carriers sell bundled routes to minimize shipper costs. 

Guo, Z.X., Wong, W.K., Leung, S.Y.S., Fan, J.T. and Chan, S.F., 2008. A genetic-algorithm-based optimization model for scheduling flexible assembly lines. International Journal of Advanced Manufacturing Technology, 36(1-2), 156-168. 

Critical path The series of activities that determines the duration of a project. It is the longest path through the project. The Critical Path Method (CPM) is a technique to predict the project s duration by analyzing the path of activities with the least amount of scheduling flexibility. (Adapted from PMBOK Guide— 2000 edition )... 

Most compensation laws use calendar days to compute the period of disability. The period does not include the day of the injury and the day an injured worker returns to work. All days between the injury and the return to work are calendar days of disability. This avoids the problem of establishing the schedule that a person would have worked. Calendar days avoids difficulties in computing benefits created by swing shifts, variable work schedules, flexible hours, holidays, plant vacations, layoffs, and the other work schedules. 

Flexibility strategy—using utilization as the lever This strategy may be used if there is excess machine capacity (i.e., if machines are not used 24 hours a day, seven days a week) and the workforce shows scheduling flexibility. In this case, the workforce (capacity) is kept stable, but the number of hours worked is varied over time in an effort to synchronize production with demand. A planner can use variable amounts of overtime or a flexible schedule to achieve this synchronization. 

Model FFR Scheduling flexible flow line with limited intermediate buffers and alternative routings... 

T. Sawik. Mixed integer programming for scheduling flexible flow lines with limited intermediate buffers. Mathematical and Computer Modeling, 31 39-52, 2000. 

Flexibility and Stress-Intensification Factors. The flexibihty factor k (>1.0) is defined as the ratio between the rotation per unit length of the part in question produced by a given moment to the rotation of a straight pipe (of the same size and schedule) produced by the same moment. A close approximation of the flexibiUty factor that agrees quite well with theory and experiment for bends is as follows ... 

Zhu, M., El-Halwagi, M. M., and Al-Ahmad, M. (1997). Optimal design and scheduling of flexible reverse osmosis networks. J. Membr. Sci., (in press). 

Therrtial Sterilization of Pouches of Beef. Methodology for food thermoprocessing in cylindrical metal containers assured food sterility in flexible packages. Beef slices (1.25 cm thick) were steam cooked to an internal temperature of 72°C and vacuum sealed in pouches to give a fill of 120 g. These pouches of beef were processed in a standard retort with complete water circulation and a superimposed air pressure of 1.7 X 105 Pa. The retort schedule—a 40-minute cook at 118°C plus come-up time followed by a 30-minute cooling time—achieved a F0 (lethality value) of 6. 

The problem could have been resolved by running two injections, either with different wavelength settings and/or with different dilutions injected, but this would have appreciably increased the workload of the technicians and the utilization factor of the instrument. Without an additional instrument, the laboratory would have lost much of its flexibility to schedule additional analyses at short notice. Another solution would have been to utilize a programmable detector that switches wavelengths between peaks, but that only works if the weakly detected component strongly absorbs at some other wavelength. 

In fact, no model can represent every aspect of an actual production process. Accordingly, the. scheduler must have some flexibility to modify the schedule proposed by the optimization algorithm, based on experience that is gained al.so at the realization of the optimal schedule. This leads to evolutionary improvement strategies starting from approximate optimization techniques. An interactive graphical presentation of the plant should enable quick intervention. 

As mentioned, intermediate storage dampens the effects of process fluctuations, reduces process cycle times, and increases flexibility in process scheduling. It is intuitively clear that the size and location of intermediate storage will influence the plant performance. Below, a basic analysis will be given for single-product plants. 

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