Final Exam Review Lean Systems • Location • Supply Chain • Inventory Management • Inventory Models • Forecasting • Sales & Operations Planning• Resource Planning • Linear Programming • Scheduling
The Exam Emphasis • First eight questions will cover general material from the first half of the course. • Review peak capacity, effective capacity and capacity cushion. • Product life cycle • Layout, Location, and Process Design • Approximately 62 multiple choice on the second half of the course.
A lean system is one in which… a. inventory is minimized b. uses a pull system of production c. both “a” and “b” d. neither • Just-in-time systems… a. use push systems of production b. are less productive than lean systems c. require short set-up times d. all of the above • The difference between push and pull systems of production is a. Push systems require more inventory. b. Pull systems require more inventory. c. Inventory amount is not a differentiating factor.
• Sears has stores all over the country and thousands of suppliers. To manage all of their inventory, they have warehouses in strategic locations throughout the country. This is called... Inventory pooling b. Forward placement • Typical of most government agencies, The College of New Jersey selects suppliers using which technique? a. Competitive approach b. Cooperative approach • Which of the approaches evaluates suppliers primarily on price? a. Competitive approach b. Cooperative approach • Which of the following is a common term for the supply chain dynamics cause by variations in demand? Variation Effect b. Expansion Effect c. Bullwhip Effect d. None of these.
• What is the cost to ship product to Sioux Falls? $300 $660 $1080 $1740 • Which method did we use to solve this location problem? a. Load Distance Method b. Linear Programming c. GIS d. Heuristic model
• Which of the following inventory models checks inventory levels on a regular schedule and replenishes the inventory each time? ABC analysis Continuous Review Periodic Review Base Stock System Visual System Optional Replenishment • Which of the above methods does Sears use? Continuous Review • Which of the following independent-demand inventory methods would be used by a company manufacturing parts for another company? EOQ EPLS Backorder Quantity Discounts
How much and how often should you order if you are using a periodic review system? You order every seven days. You do not order a fixed amount. You order the amount needed to bring your inventory level back up to the target inventory level. In the above situation, back to 2,266 units.
• It takes four weeks for Acme company to receive a shipment of containers that it uses for its product. It orders 100 containers each week. Normally it uses that many each week, but because of uncertainty in demand, it maintains 10 units in safety stock. What is Acme’s pipeline inventory, average inventory and cycle inventory? 400 in Pipeline Inventory (four orders per month); Average Inventory = 60; Cycle Inventory = 50 • Which type of operation would have higher inventory costs relative to its output? A Process-focused firm or Product-focused firm? • If you could use any of these methods, which would be best for cyclical-demand forecasting? Time-Series, Moving Averages, Exponential Smoothing, or Box Jenkins
- In order to meet demand for period 4, which sources cannot be used? Nothing from period 2 or 3. No period 1 overtime, and no inventory.
• The college actively recruits students at high schools around the state. This strategy for meeting demand is considered which of the following: Leveling ChaseReactiveAggressive • Which is the correct sequence for these planning events? MPS > MRP > Aggregate PlanMRP > MPS > Aggregate PlanMRP > Aggregate Plan > MPSAggregate Plan > MRP > MPSAggregate Plan > MPS > MRP The aggregate plan determines the general demand for groups or categories of end items. The Master Production Schedule (MPS) is the production plan for specific end items. It establishes the demand for parts and components, so it must be done before you can do the material requirements plan (MRP).
MRP In what week is the second planned order release, and what is the quantity?
Master Production Schedule When is the second MPS Start, and what is the quantity?
Master Production Schedule How much is available-to-promise in week 4? The amount you have on hand going into week 4 (115) less the amount already booked up until the next MPS quantity arrives (21). 115 - 21 = 94
Scheduling Average lateness = 16/6 = 2.67 days
Johnson’s Rule C D A F B E is also correct since A and D both have the same phase 1 time
Linear Programming A company makes two products: Engagement rings and jeweled watches. The production process for each is similar in that both require a certain number of hours of diamond work and a certain number of labor hours for gold work. Each ring takes four (4) hours of diamond work and two (2) hours in the gold shop, and each watch requires three (3) hours in diamonds and one (1) hour in the gold department. There are 240 hours of diamond labor available and 100 hours of gold department time available for the next month. Each ring (r) yields a profit of $90 and each watch (w) produced yields $100 profit Formulate the problem.
LP Formulation Each watch (w) yields $100 profit and each ring (r) yields a profit of $90 Maximize Z = 100w + 90r Subject to: (Available hours of diamond labor and gold labor) Each watch (w) requires 3 hours in diamonds and 1 hour in the gold department. Each ring (r) takes 4 hours of diamond work and 2 hours in the gold shop. There are 240 hours of diamond labor available and 100 hours of gold work time. Diamond labor 3w + 4r <= 240 hrs Gold labor 1w + 2r <= 100 hrs
Output from your LP homework Know the product mix. (Dresses and Coats) Know which resource had surplus and which was used up. Sewing time was not used up (More of it has zero value). Cutting time and Materials were used up and have value.
Sensitivity Analysis from your LP homework Know what it would take to add Skirts into the product mix.Raising the profit of skirts above $7.50 Understand why the upper boundary for Sewing time is infinity.There is unused sewing time, so more of it won’t affect the product mix.
TIPS FOR EXAMS • Get plenty of sleep the night before and exam. Being tired reduces your ability to make intelligent choices. • Don’t eat before an exam. The process of digestion takes blood away from your brain. You are always more alert when you are hungry. • Save the caffeinated beverages until right before taking an exam. Its beneficial effects are short term. • There is a reasonably good chance that the person next to you is dumber than you are, so beware of their answers.
Exam Schedule • Friday, December 6th (Last Class) 2 P.M. or 4 P.M. • Or at either of the following scheduled exam times… • Friday, December 13th at 5 P.M. • Monday, December 16th at 2 P.M. • (All exam locations are in our regular classroom.) • You have four choices for taking the final, so I don’t want anyone coming to me with a conflict. Plan ahead! One step closer to graduation...