Scheduling resource constraints

Enhanced continuous-time unit-specific event-based formulation for short-term scheduling of multipurpose batch processes Resource constraints and mixed storage policies. Ind. Eng. Chem. Res., 43, 2516-2533. 

Le Pape C. 1998. Implementation of resource constraints in ILOG SCHEDULE A library for the development of constrained-based scheduling systems, Intell. Syst. Eng., 3(2), 55-66. 

A resource-loaded schedule, including resource constraints Other constraints such as financial, political, regulatory, and logistics Start and end dates for the project... 

Ventura, J.A. and Kim, D., 2003. Parallel machine scheduling with earhness-taidiness penalties and additional resource constraints. Computers Operations Research, 30(13), 1945-1958. 

Compatible with SAV Architecture Results of a combination of analysis techniques and reviews/inspections, including modelling and simulation of the properties of the S/W architecture including the executive and scheduler, resource allocation, timing constraints and so on design analysis of dependencies between the function and the S/W architectural properties structured walk-throughs and inspections. 

Resource-constrained scheduling (RTS) Hnd a feasible (or optimal) schedule for X that obeys the precedence ccxistraints and meets the resource constraints for each functional unit type. 

Another scheduling approach is list scheduling, which schedules operations into control steps, one control step at a time. For the current control step, a list of data ready operators is constructed, containing those operators whose inputs are produced in earlier control steps, and that do not violate any resource constraints. This list is then sorted according to some priority function, the highest-priority operator is placed into the current control step, the list is updated, and the process continues until no more operators can be placed into that control step. This process is then repeated on the next control step, until the entire design is scheduled. Two common priority functions are mobility... 

Heuristic path-based scheduling First, all possible execution paths through the controlflow graph are found, and timing and resource constraints are expressed as intervals where the paths must be cut to separate the operations into states. Then heuristics are used to compute a cutting point, and cut all paths containing that point. 

Cheng-Tsung Hwang, Yu-Chin Hsu, and Youn-Long Lin, "Optimum and Heuristic Data Path Scheduling Under Resource Constraints , Proc. of the 27th DAC, pages 65-70, June 1990. 

First, uses percolation scheduling to allow data-independent operations to percolate toward earlier control steps, not considering resource constraints. To meet resource constraints, the mobility of each operation in the control step is computed, and operations with higher mobility are delayed until later control steps. 

First, an ASAP schedule is constructed, assuming infinite resources, and one cycle per operation. Then optimizations are applied, moving operations to other control steps to reduce the maximum number of operations of each type in any one control step, and grouping operations into functional units so as to have a minimum number of functional units. Uien the scheduler traverses the control step schedule, passing the operations in each control step to the data path allocator. The data path allocator tries to bind those operations using heuristics if it fails, the scheduler tries to delay operations until later control steps, and if that also fails, the user is notified that the resource constraints should be increased. 

The Control Step Scheduler (CSTEP) schedules the behavioral operations into control steps, determining the parallelism of the design. It considers the structural partitions suggested by the Architectural Partitioning tool as well as timing and resource constraints specified by the designer. 

MAHA [Parker86] performs operator allocation and binding concurrently with scheduling and schedules operators on the critical path first. It then schedules operators depending on operator mobility (called freedom in this case) and resource constraints. 

Two scheduling examples are given below. Timing and resource constraints are depicted in separate examples for clarity. 

Figure 5-9. Scheduled Multibus Write Operation 5.4.2. A Resource Constraint Scheduling Exanq)le...

The Elliptical Filter presented in Chapter 3 and for which partitioning results are presented in Chapter 4 is an interesting candidate for resource constraint information because there are many possible schedules for the data-flow. Table 5-1 shows the results of using various resource options to make schedules for the filter example. 

Using Resource Constraints to Guide the Scheduling of the Elliptical... 

This chapter has described the design and implementation of CSTEP, the Workbench scheduling tool. CSTEP was designed for speed and flexibility and supports scheduling with resource constraints and interface timing constraints. 

Projects are scheduled into the pipeline after checking the availability of resource constraints to ensure that schedules are feasible. 

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