Лист за преговор: Mastering Sales & Operations Planning Strategies

📋 Course Outline

1. Positioning and basic concepts of Sales & Operations Planning (S&OP)
2. Defining aggregate products and resource aggregation in S&OP
3. Basic S&OP strategies: Level and chase approaches with examples
4. Cost assessment and comparison of level and chase strategies
5. Hybrid S&OP strategy and fundamental optimization model formulation
6. Extensions of hybrid strategy including workforce flexibility and outsourcing
7. Application of S&OP through case studies and in-class exercises
8. Integration of S&OP with production planning inputs and course topics

📖 1. Positioning and basic concepts of Sales & Operations Planning (S&OP)

🔑 Key Concepts & Definitions

• Sales & Operations Planning : A strategic management process that determines production quantities based on forecast while planning the number of resources over a long time frame.
• Introduction : Introducing S & OP 9 / 65 The real-world process ▶ The process of S&OP is repeated on a cyclic interval and consists of the following five different steps (Wallace and Stahl 2006) 1.
• Hybrid strategy : An approach within S&OP that tailors planning modules to a firm's specific issues and regulations, combining different methods to fit company needs.

📝 Essential Points

• S&OP involves input from demand forecasting, productivity levels, and decisions on hires, fires, shift adjustments, overtime, and machine investments.
• C-level executives are typically involved in S&OP to ensure alignment with the company’s strategic plan.
• The supply & Capacity planning 4.

💡 Key Takeaway

S&OP involves input from demand forecasting, productivity levels, and decisions on hires, fires, shift adjustments, overtime, and machine investments.

📖 2. Defining aggregate products and resource aggregation in S&OP

🔑 Key Concepts & Definitions

• Product families : Groups of products that share similar characteristics, used in S&OP to facilitate planning at an aggregate level rather than focusing on individual stock keeping units (SKUs).
• Aggregate products : Artificial or grouped units representing multiple products, which can be measured in actual units, weight, volume, dollars, or fictitious units to simplify the planning process.
• Levels of aggregation : Different ways to group products or production units in S&OP, including actual units of production, weight, volume, monetary value, or fictitious aggregated units.

📝 Essential Points

• S&OP planning is based on aggregated products such as product families rather than individual SKUs.
• Resource aggregation involves combining different resource types like worker hours, machine hours, and storage volume.
• Separate S&OP processes may be needed for each resource type, requiring coordination to ensure feasibility.

💡 Key Takeaway

Master the concept of aggregation in S&OP to simplify planning by grouping products and resources appropriately.

📖 3. Basic S&OP strategies: Level and chase approaches with examples

🔑 Key Concepts & Definitions

• Chase strategy : A production approach that varies production rates to meet changes in demand, often used when inventory cannot be used or when resources are flexible and inexpensive to change.
• Illustration Basic approaches to S&OP : Examples demonstrating fundamental S&OP strategies, including level and chase approaches, with specific scenarios illustrating each approach.
• Level strategy : A production approach that fixes production rates and uses inventory and/or time to meet changes in demand, often applied when resource changes are difficult or expensive.

📝 Essential Points

• The level strategy fixes production rates and uses inventory or time to meet demand changes, suitable when resource adjustments are costly.
• The chase strategy varies production rates to match demand changes, suitable when inventory is not an option and resources are flexible.
• The level strategy calculates cumulative net demand and productivity to determine constant resource levels.
• The chase strategy adjusts resource levels period-by-period, considering starting and desired inventories.
• ▶ Chase strategy: vary production rates to meet changes in demand ▶ Often used when inventory cannot be used or when resources are flexible and inexpensive to change ▶ Examples: Restaurants, simple seasonal products such as fireworks ▶ Level strategy: fix production rates and using inventory and/or time to meet changes in demand ▶ Often used when resources changes are difficult or expensive ▶ Examples: specialized manufacturing such as cars or machinery, high automation such as semiconductor manufacturing ▶ Level strategy: fix production rates and using inventory and/or time to meet changes in demand ▶ Hybrid strategies: use a combination of chase and level ▶ Often used when some resources can change tasks and tasks can be taken over by temporary workers Hybrid strategy 42 / 65 Generic S&OP optimization model Variable definition: R+ t = Number of resources increased at the beginning of period t R− t = Number of resources reduced at the beginning of period t Rt = Number of resources during period t It = Inventory at the end of period t Pt = Production in period t Parameter definition: p = productivity per time and resource unit cI = Inventory cost per unit and time cRI = Cost to increase resource by one cRD = Cost to decrease resource by one cR = Cost to have resource for one time period dt = Demand in period t Hybrid strategy 43 / 65 Fundamental S&OP Optimization Generic S&OP optimization model (cont’d) Objective Function: min X t∈T (cRI R+ t + cRD R− t + cR Rt + cI It ) Subject to: It = It−1 + Pt − dt for t = 1...n Rt = Rt−1 + R+ t − R− t for t = 1...n Pt = pRt for t = 1...n It ≥ 0 for t = 1...n R,t , R− t , R+ t ≥ 0 for t = 1...n Hybrid strategy: Fundamental S&OP Optimization 45 / 65 Hybrid strategy for our problem Objective Function: min 6X t=1 (500R+ t + 750R− t + 10It ) Hybrid strategy: Fundamental S&OP Optimization 46 / 65 Hybrid strategy for our problem (cont’d) Subject to: I1 = 10 + P1 − 110 I2 = I1 + P2 − 120 I3 = I2 + P3 − 115 I4 = I3 + P4 − 107 I5 = I4 + P5 − 130 I6 = I5 + P6 − 100 R0 = 20 R1 = R0 + R+ 1 − R− 1 R2 = R1 + R+ 2 − R− 2 R3 = R2 + R+ 3 − R− 3 R4 = R3 + R+ 4 − R− 4 R5 = R4 + R+ 5 − R− 5 Hybrid strategy: Fundamental S&OP Optimization 47 / 65 Hybrid strategy for our problem (cont’d) Subject to (cont’d): R6 = R5 + R+ 6 − R− 6 P1 = 4.5R1 P2 = 4.5R2 P3 = 4.5R4 P4 = 4.5R4 P5 = 4.5R5 P6 = 4.5R6 It ≥ 0 for t = 1, 2, 3, 4, 5, 6 R+ t , R− t ≥ 0 for t = 1, 2, 3, 4, 5, 6 Solution $3,620 Hybrid strategy: Fundamental S&OP Optimization 48 / 65 Extending the hybrid strategy Relevant questions ▶ Should inventories be used to absorb changes in demand during planning period?

💡 Key Takeaway

Distinguish between level and chase strategies as fundamental approaches to balance production and demand in S&OP.

📖 4. Cost assessment and comparison of level and chase strategies

🔑 Key Concepts & Definitions

• Inventory cost : Costs incurred from holding inventory, including expenses for warehouse capacity, interest on loans, and opportunity costs.
• Basic approaches to S&OP : 5 + 4 + · $10
• Total cost : 5 + 4 + · $10
• Resource reduction cost : Costs arising from decreasing resources, such as severance packages and loss of reputation.

📝 Essential Points

• Resource acquisition costs include hiring and training expenses.
• Resource reduction costs include severance and reputation loss.
• Inventory costs include warehouse capacity, loan interests, and opportunity costs.
• Level strategy tends to have higher inventory costs but lower resource adjustment costs.
• ▶ Examples for costs to increase resources ▶ Workers: Job ads and drafting contracting ▶ Workers: Worker training ▶ Machines: Transportation, Installation ▶ Examples for costs to decrease resources ▶ Workers: Severance packages ▶ Workers: Reputation loss ▶ Machines: Selling efforts, removal ▶ Examples of inventory cost ▶ Warehouse capacity ▶ Interests for loans ▶ Opportunity costs ▶ Our example: ▶ Inventory costs $10/year ▶ Initial amount of resources: 20 ▶ Cost for acquiring one additional resource unit:$500 ▶ Cost for reducing by one resource unit: $750 Basic approaches to S&OP: Assessing the solution 36 / 65 Assessing the solution: Level strategy Year 2027 2028 2029 2030 2031 2032 Demand forecast 110 120 115 107 130 100 Starting inventory 10 Net demand 100 120 115 107 130 100 Cum.

💡 Key Takeaway

Evaluate S&OP strategies by analyzing trade-offs between inventory holding costs and resource adjustment costs.

📖 5. Hybrid S&OP strategy and fundamental optimization model formulation

🔑 Key Concepts & Definitions

• Hybrid strategy : a planning approach that combines level and chase methods to utilize the advantages of both, balancing steady resource levels with flexible production adjustments.

• The fundamental S&OP optimization model : a mathematical framework that includes variables for resource increases, reductions, resource levels, production quantities, and inventory levels, aimed at optimizing operational decisions.

📝 Essential Points

• The hybrid strategy integrates level and chase approaches to leverage their respective benefits, providing a flexible yet stable planning method. The core optimization model incorporates variables representing resource adjustments (both increases and reductions), resource levels, production output, and inventory status. Its objective function seeks to minimize total costs, which encompass expenses related to resource modifications, inventory holding, and resource usage. Constraints within the model ensure the balance of inventory over time, maintain resource equilibrium, respect production capacity limits, and enforce non-negativity of variables, ensuring feasible and cost-effective planning.

💡 Key Takeaway

Applying mathematical optimization to hybrid S&OP strategies enables balancing operational costs with flexibility, leading to more effective and adaptable production planning.

📖 6. Extensions of hybrid strategy including workforce flexibility and outsourcing

🔑 Key Concepts & Definitions

• Hybrid strategy : Extending the hybrid strategy 50 / 65 Group task and discussion ▶ For the country assigned to you, find out the following and collect it in the shared Excel file ▶ Maximum working time per day and week ▶ Maximum overtime per day and week ▶ Overtime compensatio
• Size of the workforce : The number of employees employed, which can be varied to accommodate demand changes by hiring, layoffs, or maintaining stability through outsourcing.
• Should demand changes be accommodated : The decision process regarding whether to adjust workforce size, use part-timers, overtime, machine idle time, or subcontracting to respond to fluctuating demand.

📝 Essential Points

• Extensions of hybrid strategy consider using part-timers, overtime, and machine idle time to absorb demand fluctuations.
• Subcontracting can stabilize workforce levels by outsourcing fluctuating orders.
• Strategic outsourcing decisions are linked to product life cycle and portfolio matrices.
• Legal and regulatory constraints, such as maximum working hours and contract terms, influence workforce flexibility options.
• ▶ Should part-timers be used, or should overtime and/or machine idle time be used to absorb demand fluctuations?
• ▶ Should subcontractors be used on fluctuating orders so a stable workforce can be maintained?

💡 Key Takeaway

Incorporating workforce flexibility and outsourcing into S&OP enhances responsiveness and cost efficiency within regulatory constraints.

📖 7. Application of S&OP through case studies and in-class exercises

🔑 Key Concepts & Definitions

• Further exercises : Additional practice problems designed to apply S&OP strategies and optimization techniques in realistic scenarios.
• Optimize the problem using : The process of applying mathematical programming to find the most cost-effective solution for S&OP planning.
• Problem using a mathematical : Formulating S&OP planning challenges as mathematical programs to identify optimal workforce and inventory plans.

📝 Essential Points

• Comparisons of strategies include calculating costs for hiring, firing, inventory, and workforce levels.
• Cost of hiring is $500, firing$1,000, and inventory per unit and month is $80.

💡 Key Takeaway

Using practical case studies and exercises enhances understanding of S&OP strategy application and cost implications.

📖 8. Integration of S&OP with production planning inputs and course topics

🔑 Key Concepts & Definitions

Production Planning & Control (PPC) objectives are specific goals related to managing production activities, such as meeting demand, minimizing costs, and maintaining inventory levels. Demand forecast uncertainty refers to the variability and potential errors in predicting future demand, which can impact planning accuracy. Management rhythm in S&OP signifies the regular, structured process that aligns different functions within an organization on a consistent, coordinated plan, ensuring ongoing synchronization of activities.

📝 Essential Points

• S&OP utilizes inputs from PPC objectives and constraints, including capacity limits, lead times, and inventory levels, to develop feasible production and inventory plans. It incorporates demand forecasts along with measures of forecast uncertainty, acknowledging the potential variability in future demand. The process translates these forecasts into volume plans that balance cost considerations with service levels, effectively managing trade-offs such as level versus chase production strategies, backlog management, and overtime. Furthermore, S&OP establishes a management rhythm that aligns various organizational functions around a single, consistent plan, facilitating coordinated decision-making. Linear programming is particularly effective for long-term S&OP due to its ability to approximate complex constraints and costs linearly, enabling efficient scenario analysis and robustness under uncertainty.

💡 Key Takeaway

S&OP acts as the integrative link that transforms demand forecasts and PPC constraints into actionable, aligned production and inventory plans, ensuring organizational coherence and responsiveness.

📅 Key Dates

Date	Event
2006	Introduction of S&OP process
2027	Assessment of level strategy costs
2028	Assessment of chase strategy costs
2029	Development of hybrid strategy optimization model
2030	Extensions of hybrid strategy including workforce flexibility and outsourcing
2031	Application of S&OP through case studies and exercises

📊 Synthesis Tables

Comparison of Level and Chase Strategies

Strategy Type	Main Characteristic	Suitable Conditions
Level	Fix production rates, use inventory to meet demand	When resource adjustment costs are high, and demand is predictable
Chase	Vary production to match demand, minimal inventory	When inventory costs are high, and resources are flexible

⚠️ Common Pitfalls & Confusions

1. Confusing aggregate products with individual SKUs
2. Ignoring the costs associated with resource adjustments
3. Overlooking the impact of demand variability on strategy choice
4. Neglecting the integration of S&OP with production planning constraints
5. Underestimating the importance of demand forecast accuracy
6. Failing to consider hybrid strategies as a flexible alternative
7. Misunderstanding the role of resource aggregation in simplifying planning

✅ Exam Checklist

1. Understand the basic concepts of S&OP
2. Differentiate between aggregate products and resource aggregation
3. Identify the characteristics of level and chase strategies
4. Evaluate costs associated with each strategy
5. Learn the formulation of hybrid S&OP models
6. Explore extensions including workforce flexibility and outsourcing
7. Apply S&OP concepts through case studies and exercises
8. Integrate S&OP with production planning inputs and constraints
9. Assess the impact of demand forecast uncertainty on planning
10. Understand the management rhythm in S&OP