Operations Management Exam 1
Process Flow Diagram
Boxes = Resources Arrows = Flows Triangles = Inventory Location
Which of the following items would be considered an input in the operations of a soft drink manufacturer? A) Brand image B) Bottling machines C) Empty bottles D) Workers
C) Empty bottles The bottle is a part of the soft drink product.
Which of the following actions does not relate to off-loading the bottleneck? A) Reassigning activities to other, non bottleneck resources B) Automating some of the activities at the bottleneck C) Increasing wages for production workers D) Outsourcing some of the bottleneck activities
C) Increasing wages for production workers
A key process metric is __________________. A) Raw materials B) Inputs C) Inventory D) Outputs
C) Inventory
What are the subcomponents of inconvenience in a customer utility function? A) Location and price B) Price and volume C) Location and time D) Time and performance
C) Location and Time
Which of the following items would be considered an input in the operations of a doctor's office? A) Examination table B) Nurse C) Needle D) Stethoscope
C) Needle The only item in the list that is a material used in the doctor's office operations is a needle. The rest of the items would be considered resources.
From the perspective of process analysis, which of the following could be appropriate flow units for a hardware store? A) Number of workers B) Number of cash registers C) Number of customers D) Number of suppliers
C) Number of customers The number of workers, cash registers, and suppliers are unlikely to change much over the course of a month and do not "flow" through the process of the hardware store.
You are sitting in a restaurant and the waiter brings you the food you ordered a while ago. If you think about you being the flow unit in the process of the restaurant, which step of this process will be downstream relative to your current position in the process? A) Waiting to order B) Being seated at a table C) Paying the bill D) Reviewing the menu
C) Paying the bill
You observe a bank and notice that a customer leaves the bank about every five minutes. These five minutes between customers are.... A) The capacity of the process B) The processing time of the last resource C) The cycle time D) The lead time
C) The cycle time
If ________________ is the constraint, we should_________________ the staffing level to raise capacity. A) demand, lower B) demand, raise C) capacity, raise D) capacity, lower
C) capacity, raise
Muri
An unreasonable amount of work, overburdening a machine or operation
Utility is composed of three components
1. Consumption Utility 2. Price 3. Inconvenience
Three major functions in any firm
1. Marketing 2. Operations 3. Finance
6 Rules for an Effective Kanban Syetem
1. Never pass on defective products 2. Take only what is needed 3. Produce the exact quantity required 4. Level the production 5. Fine-tune production 6. Stabilize and rationalize the process.
Eight Wastes
1. Over production 2. Inventory 3. Transportation 4. Motion 5. Waiting 6. Defects 7. Over processing 8. Human potential
Drivers of Consumption Utility
1. Price 2. Inconvenience
5 Step Lean Process
1. Specify value: Value is defined by customer in terms of specific products and services 2. Identify the value stream: Map out all end-to-end linked actions, processes and functions necessary for transforming inputs to outputs to identify and eliminate waste 3. Make value flow continuously: Having eliminated waste, make remaining value-creating steps "flow" 4. Let customers pull value: Customer's "pull" cascades all the way back to the lowest level supplier, enabling just-in-time production 5. Pursue perfection: Pursue continuous process of improvement striving for perfection
Three System Inhibitors
1. Waste 2. Variability 3. Inflexibility
Statistical process control (SPC)
A framework in operations management built around empirical measurement, statistical analysis of output, and outcome variables.
Resources
A group of people or equipment that transforms inputs into outputs - Help flow units move from being a unit of input to being a unit of output
Utility
A measure of the customer preference of a product or service
Consumption Utility
A measurement of how much you like a service, ignoring the effects of price and its inconvenience
Make to order
A production system in which a item's production begins after the customer for the item is known. Ex: Subway Sandwich
Make to stock
A production system in which an item's production begins before the customer for the item is known. Ex: Nike Sneakers
A Process
A set of activities that take collection of inputs, perform some work or activities with those inputs, and then yield a set of outputs
Throughput
A synonym for flow rate
Andon
A system consisting of a visible board and a cord running adjacent to the assembly line. Any employee detecting a problem can pull the cord to stop the line.
C & A Museum has three million visitors per year. Each visitor spends on average of 1 hour in the museum. What is the average number of visitors in the museum on a given day if the museum is open 300 days a year from 9 a.m. to 5 p.m.? A) 1250 B) 2400 C) 7500 D) 8000
A) 1250
You observe a long line at the airport security. The process currently is: A) Capacity-constrained B) Demand constrained C) Unconstrained D) Linearly constrained
A) Capacity-constrained
Utility is composed of the following components EXCEPT __________. A) Customer loyalty B) Price C) Inconvenience D) Consumption Utility
A) Customer loyalty
Little's Law states there is a relationship between: (Choose all that apply) A) Inventory B) Flow time C) Output D) Throughput
A) Inventory B) Flow time D) Throughput
It is election day and 1800 voters vote in their precinct's library during the 10 hours the polls are open. On average, there are 15 voters in the library and they spend on average 5 minutes in the library to complete their voting. What is the inventory of voters, the flow rate, and the flow time for each voter? A) Inventory of voters_____________________voter B) Flow rate _________________per hour C) Flow time_________________minutes
A) Inventory of voters___15___voters B) Flow rate ___180___ per hour C) Flow time ____5______minutes The flow rate is 1,800 / 10 = 180 per hour, or 180 / 60 = 3 per minute. The flow time is 5 minutes
SmartPhones are made on a 40-step assembly process. All 40 steps are connected through a conveyor belt and all of the 40 steps much work at the same rate even if some of them have more capacity than others. Is this process a machine-paced process or a worker-paced process? A) Machine-paced B) Worker-paced
A) Machine-paced
A car manufacturer has designed a "special edition" version of its popular two-door coupe. This special edition has increase horsepower compared to the standard model and a sports suspension. Which dimension of the customer utility function is particularly emphasized with the special edition coupe? A) Performance B) Fit C) Price D) Timing
A) Performance
A process has low fixed costs and high variable costs. It is currently capacity-constrained. Will the impact of an efficiency improvement be small or large? A) Small B) Large
A) Small High variable costs result in a low unit margin, which reduces the impact of each additional; customer on profitability
How does the target manpower change as the demand rate increases? A) The target manpower increases B) The target manpower stays the same C) The target manpower decreases D) Cannot determine from the given information
A) The target manpower increases
A campus deli serves 350 customers over its busy lunch period from 11:30 a.m. to 1:30 p.m. A quick count of the number of customers waiting in line and being served by the sandwich markers shows that an average of 14 customers are in the process at any point in time. What is the average amount of time that a customer spends in process? Average amount of time ____________minutes
Average amount of time __4.8____minutes Inventory = Flow rate x Flow time The flow rate is 350 customers divided by 120 minutes = 2.9167 customers/minutes 14 people in line (average inventory) = 2.9167 flow rate x flow time Flow time = 14/2.9167 = 4.8 minutes
Over the course of a 24-hour period a call center handled 1200 different calls and at noon there were 50 callers "in" the center (talking or waiting to talk to a representative). The sixth caller of the day spend 2.5 minutes with a representative. Which of the given numbers is an inventory? A) 1200 B) 50 C) 2.5
B) 50
Which of the following statements about process efficiency is FALSE? A) A process is efficient if it is able to achieve a high flow rate with few resources B) Cost of direct labor goes up if flow rate goes up C) Revenue goes up if flow rate goes up D) Cycle time goes up if flow rate goes down
B) Cost of direct labor goes up if flow rate goes up
If you maintain inventory at a constant level and keep the throughput rate constant: A) Cycle time will decrease B) Customer delivery dates become more reliable C) You are following a push operating system D) Your processes are operating under normal conditions
B) Customer delivery dates become more reliable
Is the capacity of the bottleneck larger than, equal to, or smaller than the capacity of the process? A) Larger than B) Equal to C) Smaller than D) The answer depends on the specific process under consideration
B) Equal to
Which of the following questions would be asked in a process analysis of a college admissions office? A) When was the college founded? B) How long does it take the office to process an application? C) How much is the yearly tuition at the college? D) How long does it take the average student to complete a degree program at the college?
B) How long does it take the office to process an application?
A group of workers works really hard. In fact, they work so hard that one of them claims to have an average labor utilization of 120 percent. Is that possible? A) Yes B) No
B) No
You observe a vehicle registration department at your local township. Assume that all employees are ready to work at 9 a.m. You arrive at 9 a.m. sharp and are the first customer. Is your time through the empty process longer or shorter than the flow time averaged across all customers that arrive over the course of the day? A) Longer than the average flow time B) Shorter than the average flow time
B) Shorter than the average flow time
What happens to the target manpower if the labor content is doubled? A) The target manpower increases by 50 percent B) The target manpower doubles C) The target manpower decreases by 50 percent D) The target manpower decreases by a factor of 2
B) The target manpower doubles
What is the relationship between the processing time at a resource and its capacity? A) They are the same B) They are reciprocals of each other C) They are multiples of each other D) They are not related
B) They are reciprocals of each other
Which of the following operational decisions correspond(S) to the price component of the customer utility function? A) When will the demand be fulfilled? B) What are the shipping charges to the customer? C) What is the product or service to be delivered? D) Where will the demand be fulfilled?
B) What are the shipping charges to the customer? The operational efficiency will affect the price that the firm is able to charge for it product and service to maximize its profitability.
Value of Flow Diagram
- Understand key steps to define process capacity - Evaluate lead time of product - Indentify why and how inventory accumulates
Little's Law
Inventory = Flow Rate x Flow Time
What is the maximum utilization a resource can achieve? A) A value equal to the demand B) A value equal to the capacity C) There is no maximum utilization D) 1.00
D) 1.00
Which of the following items would be considered resources in a restaurant? A) Recipes B) Food C) Brand image D) Chefs
D) Chefs
Which of the following statements about process analysis if TRUE? A) Process analysis is the backbone of a company's accounting system B) Process analysis tracks an organization's revenue and costs C) Process analysis enables a business to create demand D) Process analysis is a framework to understand an organization's detailed operations
D) Process analysis is a framework to understand an organization's detailed operations
A national restaurant chain has just opened a sit-down location at Chicago's O'Hare International Airport. Next to the sit-down location, it has also established a "to-go" section where travelers can purchase premade sandwiches and salads, as well as drinks and snacks. Which dimension of the customer utility functions is particularly emphasized with the "to-go" section? A) Performance B) Fit C) Price D) Timing
D) Timing
Which of the following inefficiencies in a grocery store's operations result from inflexibility? A) leftover fruits and vegetables B) Delivery delays from the warehouse C) A surge in customer arrivals at one time D) Employee work schedules set a week in advance
D) employee work schedules set a week in advance
Warehouse layout
Design balances space utilization and handling costs
Fixed-position layout
Design is for stationary project Ex: Ship building, Highway construction
Retail/service layout
Design maximizes product exposure to customers
Process-oriented layout
Design places departments with large flows of material or people together Ex: Hospitals, machine shops
Product-oriented layout
Facility organized around product, design minimizes line imbalance Ex: auto assembly line, brewery, paper manufacturer
"Firm A Pareto dominates Firm B" means that Firm A's product or service is inferior to that of Firm B on all dimensions of the customer utility function. True or False
False
A flow unit is generally associated with the inputs of a process True or False
False
A resource with a utilization of less than 100% cannot be the bottleneck True or False
False
A resource with setups can achieve a flow rate that is equal to its capacity True or False
False
Balancing a process with a fixed sequence of activities will achieve a higher average labor utilization than balancing a process with no fixed sequence of activities. True or False
False
Costs of direct labor goes up whenever labor content goes up True or False
False
Cycle time is the time between when an order is placed and when it is completed True or False
False
Setup involves different amounts of time depending on the actual number of units to be made True or False
False
Throughput, sometimes referred to as output rate, is expressed in units produced per hour. True or False
False
When an operation improves its efficiency, its revenue will always stay constant, while its costs will go down. True or False
False Efficiency can result in higher revenue as well because the operation can serve more customers
A computer server experiences large fluctuations in the amount of data requests it receives throughout the day. Because of this variation, Little's Law does not apply. True or False
False Little's Law applies even if there are fluctuations in inventory, flow rates, and flow times
Little's Law is very general, so it is not necessary that flow rate and flow time use the same time units True or False
False The same time units must be used for the flow rate and the flow time.
Pareto Dominated
Firms product is inferior to one or multiple competitors on all dimensions of the customer utility function
Poka-yoke
Fool proofing an operation to avoid the recurrence of defects.
Consider the baggage check-in process of a small airline. Check-in data indicates that from 9-10am, 240 passengers checked in. Moreover, based on counting the number of passengers waiting in line, airport management found that the average number of passengers waiting for check-in was 25. How long did the average passenger have to wait in line?
How long does the average passenger have to wait in line?__6.3_____minutes Inventory = Flow rate x Flow time 25 people in line (average inventory) = 240 customers / 60 minutes (flow rate) x flow time Flow time = 6.3 minutes
LaVilla is a village in the Italian Alps. Given its enormous popularity among Swiss, German, Austrian, and Italian skiers, all of its beds are always booked in the winter season and there are on average 1200 skiers in the village. On average, skiers stay in LaVilla for 10 days. How many new skiers are arriving, on average, in LaVilla every day?
How many new skiers are arriving, on average, in LaVilla every day?___120______skiers 1,200 beds divided by 10 days = 120 new skiers per day
Patients take a drug for severe acne for 6 months and there are 60,000 new patients each month. How many patients are taking this drug on average at any given time?
How many patients are taking this drug on average at any given time? ___360,000______patients 6 months (flow time) x 60,000 new patients per month = 360,000 patients
One of the chair lifts at a ski resort unloads 1900 skiers per hour at the top of the slope. The ride from the bottom to the top takes 19 minutes. How many skiers are riding on the lift at any given time?
How many skiers are riding on the lift at any given time? ____602___skiers 1,900 skiers divided by 60 minutes per hour (flow rate) x 19 minutes (flow time) = 602 skiers
Inflexibility
Inability to adjust to either changes in the supply process or changes in customer demand
Inefficient
Inefficiency is the gab between the firms current position and the efficient frontier
Heijunka
Japanese technique of achieving level output flow by coordinated sequencing of very small production batches throughout the manufacturing line in a lean production or just in time (JIT) system.
CodeDeskInc matches programmers with freelance jobs. It has 34 employees who staff its online chat room. It receives, on average, 235 chat requests per hour, and the average chat session takes 5 minutes to complete. On average, how many chat sessions are active (i.e., started but not completed)?
On average, how many chat sessions are active? ____20_____chat sessions Flow rate = 235 chats divided by 34 employees = 6.91 Flow time = 5 minutes divided by 60 minutes = 0.083 hour Inventory = Flow Rate x Flow Time, 6.91 x 0.083 = 0.5760 x 34 employees = 20 chats
Downnstream
Parts of the process at the END of the process flow
Upstream
Parts of the process that are at the BEGINNING of the process flow
The 4 - P's of Toyota
Philosophy, Process, People/Partners, and Problem Solving
Variability
Predictable or unpredictable changes in the demand or the supply process -customer arrivals, requests, behaviors - Time to serve a customer, disruptions, defects
Kanban
Production and inventory control system in which production instructions and parts delivery instructions are triggered by consumption downstream.
Mass Customization
Production of personalized or custom-tailored goods or services to meet consumers' diverse and changing needs at near mass production prices. Ex: Paris Miki Eyeglasses, Dell Computers, M&Ms
6S
Sort, Safe, Straighten, Scrub, Standardize, Sustain
Robust
The ability of a process to tolerate changes in input and environmental variables without causing the outcomes to be defective.
Waste
The consumption of inputs and resources that do not add value to the customer - wasting food - wasting employees time - giving consumers something they don't value
Capabilities
The dimensions of the customers utility function a firm is able to satisfy
Process Capacity
The maximum flow rate a process can provide per unit of time. It determines the maximum flow rate a process can provide per unit of time. Thus it determines the maximum supply of the process.
Trade-offs
The need to sacrifice one capability in order to increase another one
Inventory
The number of flow units within our process Ex: 12.5 mothers in the hospital at any given time
Kaizen
The process of making small changes to the process with the goal of eliminating waste
Flow Rate
The rate at which the flow units travel through the process. Must have per unit of time Ex: The average stay in the hospital for a woman is 2.5 days - people per month - dollars per week - kilograms per hour
Target manpower
The ratio between the labor content and the takt time determines the minimum number of resources required to meet demand. This minimum does not have to be an integer number and it is assumes all resources are perfectly utilized. = Labor Content / Takt Time
Takt time
The ratio between the time available and the quantity that has to be produced to serve demand. = Available time / required quantity
Pull system
The resource furthest downstream (closest to the market) is paced by market demand. In addition to its own production, it also relays the demand information to the next station upstream, thus ensuring that the upstream resource also is paced by demand.
Efficient Frontier
The set of firms that are NOT Pareto Dominated
Flow Time
The time a flow unit spends in the process, from start to finish Ex: The average birth rate at a local hospital is 5 births per day
Processing Time
The time it takes a resource to complete one flow unit
The Objective of Lean
To increase value added work and reduce waste to increase throughput, lower cost and improve quality
A batch size should be chosen for a process with setups to make a trade-off between capacity and inventory True or False
True
A bottleneck is the resource with the lowest capacity in a multistep process True or False
True
Automating some activities at a non bottleneck resource increases the amount of idle time for that resource without making the process more efficient True or False
True
C & A Bakery serves 200 customers in 10 hours. On average there are five customers in the bakery. This means each customers spends on average 15 minutes in the bakery. True or False
True
If the takt time is shorter than the cycle time, the process needs to run faster. True or False
True
Revenue cannot be increased with an efficiency improvement on a demand-constrained process True or False
True
Takt time matches cycle time if supply matches demand True or False
True
The capacity of a resource with setups is dependent on the batch size True or False
True
Mura
Unevenness in flow
Jidoka
Upon detection of a problem, shutting down the machine to focus on a human intervention, which in turn triggers process involvement.
Visual Controls
Visual control are means, devices, or mechanizms that were designed to manage or control our operations (process) Ex: Signs, Shadow Board, Visual Task Management
Process Analysis
a rigorous framework for understanding the detailed operations of a business that can be used for everyone running a business.
Product Process Matrix
a tool for analyzing the relationship between the product life cycle and the technological life cycle
Value Stream Mapping (VSM)
a tool used to see and understand the flow of material and information as a product or service makes its way through the value stream
Effective capacity
achievable level under normal conditions, for an extended time
Capacity
amount of input that can go into or the amount of output that can be created by a process, at a given level of resources over a given time period - (For One-Step Process) Maximum number of flow units that can flow through that resource per unit of time Capacity = 1/Processing Time
Bottleneck
any resource whose capacity is equal to or less than the demand placed upon it
Maximum Capacity (Designed or Rated Capacity)
highest achievable level under ideal conditions, for a limited time
Utilization
how much available capacity is actually used - Measures how busy the resources of the process are
Efficiency
how much of effective capacity is actually used
Continuous Processing
involves the product flows continuously rather than being divided into discrete units. A basic material is passed through successive operations and eventually emerges as one or more products. Ex: Soft drinks, granola bars
Assembly Line Processing
laborers generally perform the same operations for each production run in a standard and hopefully uninterrupted flow. Generally heavily automated. Ex: Car Manufacturer, Pancheros, Subway
Cellular Manufacturing
produces families of parts within a single line or cell of machines Ex: Electronics Manufacturing, Pella Windows
Batch Processing
provide similar items on a repeat basis, usually in larger volumes than that associated with job shops. Ex: Classrooms, Bakery, Cinema
Just in time production
supplying a unit of demand when and where it is needed avoiding unnecessary inventory
Flow Unit
the basic unit that moves through a process Ex: Births per day - calls at a call center - patients in a hospital
Operations Management
the management of processes used to design, supply, produce, and deliver valuable goods and services to customers
Demand Rate
the number of flow units that customers want per unit of time
Job Shop Production
the producer of unique products. Ex: Machine shop, Hospital, Bank
Cycle time
the time between completing two consecutive flow units
Lead time
the time between when an order is placed and when it is received
Processing Time
the time it takes a resources to complete one unit flow