Usage Use the LP Planning (linear programming planning) page when you
want to model your supply chain and compute schedules that optimize a selected objective while satisfying a set of specified constraints on operations. The LP Solver doesn’t ensure a material- or capacity- feasible plan. You can use LP Solver solutions to feed into the Feasible Planning Solver to obtain a feasible plan.
Object PL_GEN_LP Component
Navigation Plan Production, Process Production Plan, Process, Generate Plan,
LP Planning
Prerequisites If you are going to generate a plan immediately, a Planning server and
Process server must be running. Access
Requirements
Generate Plan - LP Planning page
The following fields are common to multiple pages and are defined in the preface of this PeopleBook in PeopleBooks Standard Field Definitions: User ID and Run Control ID.
Linear programming provides a global view of the supply chain problem. The LP Solver models the planning constraints into a system of linear inequalities and then solves this linearly relaxed system to obtain an optimal solution. While the solution contains global and optimal information about the problem, it is a linear estimation, containing little task-specific information. To address this, the solver automatically runs a post-processor that provides a real, task-based solution for planning.
The post-processor is based on logic and procedures that build a task-level schedule from aggregate solutions, such as sourcing, equipment selection, and general timing. The aggregate solution is converted into a task-specific plan on a detailed timeline. This makes it possible for the features of the LP Solver to work with the other solvers.
After you make your selections on this page, click the Run LP button if you want to generate a plan immediately. PeopleTools uses the current settings in the Production DataLink along with any changes you make to solvers in the Generate Plan option to run the plan.
You can temporarily change which host machine or database you are linked to. For example, you might have established a test database or work with a different set of data. Using the Planning Server option, you can change among your host machines to select the server containing the database you want to use to generate the plan. You don’t have to use the Define Business Rules option to make the change; however, only server templates that have been defined by that option are available here. If you want to define a new server setting template, use the Planning Server Definition page.
Click the Change Server Settings button to change the settings for a server temporarily. For more information about using the Change Server Settings button, see the “Managing the Master and Material Plans”.
Use the Carrying Cost Rate (%/year) field to define the annual percentage rate the solver uses to calculate the cost of maintaining the inventory. The cost is based on a percentage of the average inventory value for the year. This value is set during the Production DataLink process.
The default value for the field is 10 if values haven’t been defined using PeopleSoft Enterprise or Production Planning. You can’t change the value using the Generate Plan page.
Use the Late Shipment Penalty (%/day) field to define the percentage it costs your business on a daily basis to miss a shipment date. The percentage is based on the standard cost of the item.
The default value for this field is 0.1; however, you can change the value for an LP Solver run.
The Number of Daily Periods field represents the total daily periods from the early fence that
you want to include in the plan. The default value for this field is 7. The smaller the number of
periods you plan for, the more realistic you make your plan.
The Number of Weekly Periods field represents the total weekly periods following daily periods
that you want to include in your plan. The default value for this field is 4. You can use this field
to plan implicitly for monthly buckets as well. When the late fence exceeds the last weekly period, then the LP Solver uses monthly buckets for the rest of the periods.
We recommend that you don’t enter more than 30 total periods in order for the LP Solver to find optimal plans for large-scale problems. The total is the sum of daily and weekly periods.
After the LP Run
Select the Run Feasible Planning after LP check box to invoke the Feasible Planning Solver automatically after you run the LP Solver. Use the LP Solver to generate an initial plan when there are more complex trade-off decisions in the supply chain network. These decisions might include sourcing decisions, alternate resources, item substitution, or material allocations based on demand priority. This is a regenerative process where the system reschedules all independent demands to their due date and deletes all tasks with a status of Planned. We recommend that you run the Feasible Planning Solver after you run the LP Solver to create a plan that is feasible. For more information about using the LP Planning Solver to generate a master or material plan, see “Setting Up the Production DataLink”.
The master plan enables you to plan for finished goods and key component materials. You can use the master plan to ensure that top-level material and capacity requirements have been
accounted for before exploding lower-level material and capacity requirements. With PeopleSoft Supply Chain Planning, you can create and maintain the master plan in either Enterprise Planning or Production Planning.
The material plan enables you to plan for subassemblies and lower-level raw material
requirements. The material plan uses the results of the master plan to determine the requirements for meeting the master plan.
You use PeopleSoft Production Planning to create and maintain the master and material plans. Because a Production Planning model contains both master- and material-plan items, the plans are similar in the information they produce and display. This chapter uses the material-plan pages to describe how you use both plans; however, differences between the two plans are noted when they occur.