Giới thiệu về quy trình quản lý dịch vụ ô tô tại đại lý Toyota (Tài liệu tiếng anh)

TABLE OF CONTENT
CHAPTER 1: INTRODUCTION TO THESIS..................................................................1
1.1. Overview................................................................................................................. 1
1.2. The object and scope of research.............................................................................1
1.2.1. Object of Research...........................................................................................1
1.2.2. Scope of the Research......................................................................................2
1.3. Research methodology............................................................................................2
1.4. Outline of thesis......................................................................................................2
CHAPTER 2: THEORETICAL BASIC.............................................................................3
2.1. Introduction to operations management..................................................................3
2.1.1. Introduction......................................................................................................3
2.1.2. The Customer’s View of The World.................................................................3
2.1.3. A Firm’s Strategic Trade-Offs...........................................................................4
2.1.4. Overcoming Inefficiencies: The Three System Inhibitors................................5
2.1.5. Conclusion.......................................................................................................6
2.2. Introduction to processes.........................................................................................6
2.2.1. Process Definition, Scope, and Flow Units......................................................6
2.2.2. Three Key Process Metrics: Inventory, Flow Rate, and Flow Time.................9
2.2.3. Little’s Law – Linking Process Metrics Together...........................................10
2.2.4. Conclusion......................................................................................................11
2.3. Process Analysis....................................................................................................11
2.3.1. How to draw a Process Flow Diagram...........................................................11
2.3.2. Capacity for a One-Step process....................................................................16
2.3.3. How to Compute Flow Rate, Utilization, and Cycle Time.............................16
2.3.4. How to Analyze a Multistep Process and Locate the Bottleneck....................18
2.3.5. The Time to Produce a Certain Quantity........................................................18
2.3.6. Conclusion.....................................................................................................19
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2.4. Process Improvement............................................................................................19

2.4.1. Introduction....................................................................................................19
2.4.2. Measures of Process Efficiency......................................................................20
2.4.3. How to Choose a Staffing Level to Meet Demand.........................................22
2.4.4. Off-Loading the Bottleneck............................................................................23
2.4.5. Conclusion.....................................................................................................23
2.5. Process analysis with multiple flow units..............................................................23
2.5.1. Introduction....................................................................................................23
2.5.2. Generalized Process Flow Patterns.................................................................24
2.5.3. Attrition Losses, Yields, and Scrap Rates.......................................................24
2.5.4. Flow Unit – Dependent Processing Time.......................................................25
2.5.5. Conclusion.....................................................................................................28
CHAPTER 3: RESEARCH METHODS..........................................................................28
3.1. Research in operations management.....................................................................28
3.1.1. The aim and the scope of research..................................................................28
3.1.2. Roles of researcher.........................................................................................28
3.1.3. The research process......................................................................................29
3.1.4. Research as contribution to knowledge..........................................................30
3.1.5. What to research for academia and practice?..................................................31
3.1.6. Research quality.............................................................................................32
3.2. The research process.............................................................................................33
3.2.1. Contributing the knowledge...........................................................................33
3.2.2. Using literature to develop the research topic.................................................34
3.2.3. Considerations in choosing a research approach............................................35
3.3. Surveys..................................................................................................................37
3.3.1. The survey research process...........................................................................37
3.3.2. What is needed prior to survey research design?............................................37
3.3.3. Data Analysis and Interpretation of Results....................................................39
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3.3.4. Questions to Check the Quality of an Ongoing Survey Research...................39
3.4. Case Research.......................................................................................................41
3.4.1. Introduction....................................................................................................41
3.4.2. When to use case research..............................................................................41
3.4.3. The Research Framework, Constructs and Questions.....................................43
3.4.4. Choosing Cases..............................................................................................44
3.4.5. Developing Research Instruments and Protocols............................................45
3.4.6. Conducting the Field Research.......................................................................47
3.4.7. Reliability and Validity in Case Research.......................................................50
3.4.8. Data documentation and coding.....................................................................50
3.4.9. Analysis..........................................................................................................51
3.4.10. Conclusion....................................................................................................52
3.5. Longitudinal field studies......................................................................................52
3.5.1. Introduction to the longitudinal field study.....................................................52
3.5.2. Setting up the longitudinal field study............................................................53
3.5.3. Collecting data in the longitudinal field study................................................53
3.5.4. Analyzing longitudinal field data....................................................................53
3.5.5. Building theory from longitudinal field studies..............................................53
3.5.6. Evaluating theory from longitudinal field studies...........................................54
3.6. Modelling and simulation......................................................................................54
3.6.1. Introduction....................................................................................................54
3.6.2. Origins and development of model-based research in OM.............................54
3.6.3. Methodologies in quantitative modelling.......................................................55
3.6.4. Conclusion.....................................................................................................57
CHAPTER 4: DATA ANALYTICS..................................................................................58
4.1. Type of data we use...............................................................................................58
4.1.1. Categories of Descriptive Data.......................................................................58

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4.1.2. Measure of central tendency the mean median mode and their interpretations
and calculations........................................................................................................59
4.1.3. Measure of spread in data, the range, interquartile – range, standard deviation
and variance.............................................................................................................61
4.2. Relationship between variables.............................................................................62
4.2.1. The covariance and correlation measures.......................................................62
4.2.2. Probability and Random Variables; Discrete Versus Continuous Data,
Probability Density Function and Area Under the Curve.........................................64
4.2.3. The Normal Distribution (Bell Curve), Norm.Dist, Norm.Inv Functions in
Excel........................................................................................................................65
4.3. Distribution and probability..................................................................................68
4.3.1. The binomial and Poisson distributions..........................................................68
CHAPTER 5: CONCLUSION AND IMPROVING SUGGESTIONS............................71
5.1. Conclusion............................................................................................................71
5.1.1. Summarizing the data in separate sub-processes............................................71
5.1.2. Analyzing and Finding the Bottlenecks of the sub-processes.........................74
5.1.3. Detailed analysis of bottleneck process..........................................................75
5.2. Improving suggestions for Car Dealer...................................................................77
5.2.1. Process...........................................................................................................77
5.2.2. Quality............................................................................................................80

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LIST OF FIGURES
Figure 2.1 Consumer Utility, its components and subcomponents.....................................3
Figure 2.2 Express Maintenance Process...........................................................................7
Figure 2.3 Quick Repair Process........................................................................................8
Figure 2.4 Toyota Bien Hoa Service Process.....................................................................8

Figure 2.5 Flow Unit of a Process......................................................................................9
Figure 2.6 General Process Flow Diagram.......................................................................13
Figure 2.7 Activities at Reception sub-process of EM service.........................................14
Figure 2.8 Complete Process Flow Diagram....................................................................16
Figure 3.1 Different process paths in case research..........................................................43
Figure 3.2 Choice of number and type of cases................................................................44
Figure 3.3 Reliability and validity in case research..........................................................50
Figure 3.4 Research Model..............................................................................................56
Figure 4.1 Positive covariance and Negative covariance.................................................63
Figure 4.2 Covariance formula Copyright® eduCBA...................................................63
Figure 4.3 Example of Continuous Data (Copyright®: towarddatascience)....................65
Figure 4.4 Example of Normal Distribution (Copyright®: alamy)..................................66
Figure 4.5 Bell curve properties of the distribution (Copyright®: alamy).......................67
Figure 4.6 Poisson distribution.........................................................................................70
Figure 5.1 Histogram of Reception..................................................................................71
Figure 5.2 Histogram of EM............................................................................................72
Figure 5.3 Histogram of General Jobs..............................................................................73
Figure 5.4 Histogram of Delivery....................................................................................73
Figure 5.5 Required time of each sub-process.................................................................74
Figure 5.6 Time required for each sub-process................................................................75
Figure 5.7 Time required for each task at Express Maintenance station...........................76
Figure 5.9 Time required for each task at General Jobs station........................................77
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LIST OF TABLES
Table 2.1 General Workflow Example.............................................................................20
Table 2.2 Definitions of Measures...................................................................................21
Table 2.3 Cycle Time of Sub-processes............................................................................22
Table 2.4 Demand for agents at 10-hour shift..................................................................26

Table 2.5 Calculating the time required............................................................................26
Table 2.6 Computing Demand of each Sub-process.........................................................27
Table 2.7 Implied Utilization of each sub-process...........................................................27
Table 4.1 Example of calculating Mean...........................................................................60
Table 4.2 Example of Discrete Data.................................................................................65
Table 5.1 Calculated data of each task.............................................................................76
Table 5.2 Time-consuming of each task at GJ sub-process..............................................77

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ABSTRACT
BP – Body and Paint
EM – Express Maintenance
GJ – General Jobs
ODO – Odometer or Odograph
OM – Operations Management
PMF – Probability Mass Function
STDEV – Standard Deviation

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CHAPTER 1: INTRODUCTION TO THESIS
1.1. OVERVIEW
In the new millennium, operations management service plays a crucial role in every
entrepreneurs, modernized industries and advanced companies all around the globe.
It is the obvious fact that service not only support any businesses but also enhance and
develop their quality for customers’ utility.
Advanced operations mean teaching young readers the content they need in today’s

world, not the world of 40 or 50 years ago. Therefore, “services” and “global” are
incorporated throughout, rather than confined to dedicated chapters. Manufacturing
cannot be ignored, but again, the emphasis is on contemporary problems that are
accessible and relevant to young learners. For instance, Toyota Bien Hoa station is
important for the functioning production, but young generation no longer need to be able
to replicate those calculations. Instead, they should acknowledge how to identify the
bottleneck in a process and use the ideas from the Toyota Production System to improve
performance. And readers should understand what contract manufacturing is and why it
has grown so rapidly. Summary, we want young readers to see how operations influence
and explain their own experiences.
General view of operations means educating young readers much more than how to do
math problems. Instead, the emphasis is on the explicit linkages between operations
analytics and the strategies organizations use for success. For instance, we want young
generation to acknowledge how to manage inventory. In other words, general view of
operations supplies readers with a brand new, broader perspective into the organizations
and markets they interact with every day. We strongly believe that operations
management is as relevant for a young adult’s future career as any other topic taught in a
business school. New companies and business models are created around concepts from
operations management. Established organizations live or die based on their ability to
manage their resources to match their supply to their demand. One cannot truly
acknowledge how business works nowadays without understanding operations
management. To be a bit colloquial, this is “neat stuff,” and because the young will
immediately see the importance of operations management, we hope and expect they will
be engaged and excited to learn.
1.2. THE OBJECT AND SCOPE OF RESEARCH
1.2.1. Object of Research
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Data Analysis.
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Automotive Operation Management service theory.

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Research methods about collecting figures in sub-processes.
1.2.2. Scope of the Research

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Collecting and analyzing figures from three main sub-processes.

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Acknowledging the first five chapters from Operation Management material.

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Learning Data Analysis to apply on Automotive Service.

1.3. RESEARCH METHODOLOGY
Research Method is the ideal way to observe and collect data correctly. We will
demonstrate with detail in Research Method section in this graduated thesis.
1.4. OUTLINE OF THESIS
Chapter 1: Introduction to Thesis
Chapter 2: Theoretical Basic
Chapter 3: Research Method

Chapter 4: Data Analytics
Chapter 5: Conclusion and Improving Suggestions

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CHAPTER 2: THEORETICAL BASIC
2.1. INTRODUCTION TO OPERATIONS MANAGEMENT
2.1.1. Introduction
Generally, in this very first phase, we would like to emphasize the main elementary
difficulties of connecting supply to demand. This beginning desire us to focus on
demand, what do purchasers really want? After the demand is acknowledged, we take a
careful look at the aspect of a solid experiment to deliver the demand, we look at the
supply procedure. Following that, we consider the operational choices, a firm must
accomplish to grant consumers with what they want at a minimum charge. At the present,
regularly, customers need better, more development and improvement in products for
affordably cheap costs. However, in the particle modern world, this happening maybe not
often be elementary to settle. Usually, a consecutive segment in this first phase discuss
about overwhelming three main prevention that maintain the service from bringing
outstanding merchandises at low expend. In addition, these avoidances, the activity also
requires creating trade-offs and equity multiple, promisingly competing objectives. We
come to an end in this introductory stage by clarifying what occupation suited to
operations administration look alike and by supplying a short and solidified general view
of service control.
2.1.2. The Customer’s View of The World

Figure 2.1 Consumer Utility, its components and subcomponents
Utility – A certain amount of preference that buyers really want for any product or
service. Consumers buy the product or service that maximizes their utility. Most
customers are looking for maximum utility. For instance, customers want to purchase a

cheap, spacious, durable and reliable vehicles, which most of them are Toyota brand.

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Consumption Utility – Your ideal measure of how much level you want a product or
service, and not caring the effects of charge, cost and the uncomfortable of getting a
certain product or service. For example, a random person buys you a full Toyota repairing
service package at the Sub-process near the place you live.

Performance – A sub-factor of the using utility that seizes how much an average person,
who consumes, really wants for a given service or product. For instance, most of young
consumers really love to buy and drive a 2020 Toyota Supra supercar.

Fit – A sub-element of the devouring utility that takes up how well the product or service
connects to the exclusive characteristics of a certain customer. For some people, they just
want a spacious and luxurious SUVs, while some other prefer small, compact, powerful
sedans.

Price – The full amount of charge of receiving the service or having the product. For
instance, the total bill for purchasing the brand-new Toyota Camry, which including taxes
and number plate, is approximately 1.2 billion VND.

Inconvenience – The devaluation in utility that results from the achievement of
purchasing the merchandise or service. Example like customers in District 6 want to buy
a certain service package at Toyota Bien Hoa center but it is too far away from their
destination.

Location – The accommodation where a consumer can buy or obtain a product or
service. For example, Toyota Bien Hoa center is the ideal place in Bien Hoa city for

repairing or buying new Toyota vehicles.

Timing – The amount of period that flows away between the purchaser ordering service
or a product and the consumer obtaining service or the merchandise. It’s like Flow Time
from vehicle’s repaired order is made to the car is well-oiled.
2.1.3. A Firm’s Strategic Trade-Offs
In the new millennium, all our new or loyal purchasers would be amazed because we
deliver and bring out excellent products or assistance and facility, we would adjust
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customers to the miscellaneous requirements of each and every our buyers, we would
distribute to customers frequently anytime and anyplace the consumer feels like, and we
would also suggest everything, every item at very minimum and reasonable price.
Unluckily this seldom happens, with a little percent. For instance, competing in sports
entertainment, it is nearly impossible that you will be the best at wrestling, running,
shooting, tennis, basketball, volleyball, soccer, gymnastics, and so on. The same case
covers manufactures, they cannot be good at entirety. Producers and manufactures have
the abilities that let them to accomplish well on some but not all the sub-factors making
up the purchasers’ serviceableness function.
So, manufactures and producers hardly be good at all every aspect, as the matter of fact;
they must cope with trade-offs in their business and organizations. For more detail, they
trade off consumption utility and the charges of delivering the merchandises or services.
It is also the same with this challenge, they trade off the inconvenience and
uncomfortable of purchasing their services or products with the price of supplying them;
and, as the Toyota competes with Honda for instance demonstrated, they even have to
deal with trade-offs among non-cost-related sub-elements of the utility function.
To put it briefly, you can wonder about three main techniques in which operations
administration can be enhanced a business or organization as it seeks to connect almost
perfectly supply with demand:

 Make trade-offs among the aspects and elements of accomplishment.
 Lower incompetence and inefficiencies in case the business does not have to
eliminate one performance aspect versus another, thereby moving toward the
productive frontier.
 Renew, redevelop and improve the operations, approaching to a shift in the
effective boundary.
2.1.4. Overcoming Inefficiencies: The Three System Inhibitors
Waste corresponds to all the consumption of inputs and resources that do not add value
to the customers. Because waste consumes inputs and resources, waste is costly. Most of
eateries must get rid of redundant food that has been bought and maintained but has not
been performed before it is out of date. Some worse scenarios, food is cooked properly
and repaired but then not been purchased, costing the eatery resources and input.
On the other hand, variability is the second system inhibitor. Variability correlates with
changes in either supply or demand over time. Think about buyer demand draws parallel
with the variability first. We have the ability of distinguishing between the following
forms of demand variability:
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 Customer arrivals: Purchasers may arrive at any period of the day when they
want. However, some of this variability is easy to forecast and predict. For
instance, a random eatery has more order and demand at early afternoon than
at 16:00. But differences come in every day and it is almost impossible to
have a perfectly advanced plan.
 Customer requests: It is quite challenging because we also don’t really know
what exact menu item a random consumer feels like to have. Additionally,
the quantity of purchasers’ demand food on a certain day unpredictable to us.
Manufactures also have to deal with variability in their supply too. This could illustrate
in the following forms:
 Disruptions: Occasionally, an employee works faster than normal; also, on

other occasion, he performs slower. There is also a change that he is absent
too. There are a lot of reasons why workers might take a day off, such as
terrible weather, illness, family’ problems and so on. This situation is also the
same as some devices might be broke down and electronic systems could
display slowly, or a repair is required.
 Defects: A business cannot be developed easily in a straight line, sometimes
things have to go in other direction in a negative way. Chiefs cook the wrong
customer order, food gets undercooked, blue or not season properly, and pay
checks can also goes wrong. Therefore, these situations may grow more
variability in the operation.
We define flexibility as an operation’s ability to react to variability. Inflexibility, which is
our third process inhibitor, is thus the inability of an operation to change in response
quickly and cheaply to new information.
2.1.5. Conclusion
The only thing that matter in operations control is serving customers their ideal services
or products while utilizing and taking good advantage of facilities, inputs and resources
so that charges are minimum enough to created value to the company. Connecting supply
to demand while making benefit is never easy and sometimes hardship occurs due to the
fact that the three system inhibitors happens all the time and manufacturers have to deal
with them. Self-wonder what the buyer really feels like and what maintains us from
suiting this demand to a supply that we can somehow supply at reasonably affordable low
price to still create value to company.

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2.2. INTRODUCTION TO PROCESSES
2.2.1. Process Definition, Scope, and Flow Units
Process is an arrange of actions which conclude of intakes, processing stage or
operations with those inputs, and then produce a group of results.

For instance, Express Maintenance repaired-category at Toyota in Bien Hoa industrial
city receives Toyota vehicles (inputs); carries out several advanced techniques, depend on
conditions and vehicle’s odometers, like changing engine oil, filling coolant, cleaning air
filter, replacing old tires with new ones; and then sends them back to drivers or owners
(output), hopefully with better repair quality or customer service to enhance customer
satisfaction. This can appear like a very complicated process. There are many people
involved, such as Customers, Receptionist, Service Advisors, Technical Advisors, and
Technicians. There are various pieces of complex equipment and there are also a couple
of rooms, including a waiting room, customer service room and procedure areas. Despite
the complication of an Express Maintenance stage, if we get down to business and look at
the general picture, the complication can be taken down to the Figure 2.2.

Figure 2.2 Express Maintenance Process

Process Flow Diagram stimulates the processing stage by some basic graphics, for
instance squares as facilities or resources, arrows consider as flows, and triangles as
capacity or inventory accommodation.
This Figure 2.2 is known as a process flow diagram because it demonstrates a graphical
representation of the repair process. It has some components. The inputs to the process
are illustrated as arrows flowing into the process and outputs are shown as arrows
flowing out of the process. Rectangular boxes within the process flow diagram can be
recognized as resources. For instance, there is a single resource, the quick painting
repaired category, but later, process flow diagrams can have multiple resources with the
output of some resources used as the inputs to other resources.
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Resource is a certain quantity of people and/or devices, equipment, or tools that make
intakes into results. We can see that at a simple stage, the Express Maintenance takes in
cars that need repair as inputs, then performs several tasks on them when they are in the

stage, and then treated vehicles leave as the outputs. This describes the Express
Maintenance’s process scope.

Process Scope is an arrange of operations and processes which consist of the process.
The scope of this process is defined to conclude the entire Express Maintenance stage.
This is suitable if we take full responsibility of the whole stage and we want to keep track
of how the entire Express Maintenance process is operating. However, the other scopes
are certainly reasonable, relying on your point of view and positions. For specific
instance, if you are an EM Technician who assists with changing engine oil, you may
only focus on the portion of the process that takes act in changing engine oil. In that
scenario, your process flow diagram perhaps looks slightly different like this in Figure
2.3.

Figure 2.3 Quick Repair Process

If the scope can be compacted, it can also expand. We have kept the unchangeable inputs
and outputs, but our scope has normally focus on just a single type of procedure. But
what if you are the president or manager or maybe people play crucial roles in the
company, specifically you are the vice-president of Toyota Bien Hoa. Then your process
could be expressed with the “advanced phase” map demonstrated in Figure 2.4.

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Figure 2.4 Toyota Bien Hoa Service Process

Moreover, the process scope, to start with acknowledging and analyzing a process, a flow
unit must be defined. The flow unit is the basically main unit that travels through a
process. It is usually involved in the outputs of a certain process. In the situation of the
Express Maintenance process, an obvious flow unit is a “Toyota vehicle” because the

main purpose of the Express Maintenance is to repair and replace old components for
cars quickly.

Flow Unit is the given item or unit of analysis that we see in a process analysis.
Measuring and analyzing some key performance variables for the process are ready to be
begin when only the scope of the process and its flow unit are determined.

Figure 2.5 Flow Unit of a Process
Figure 2.5 demonstrates possible flow units and three other processes. In each case, it is
not hard to imagine that the flow unit could be something different than what is listed.
For instance, the flow unit in a brake repairing repaired category could be a vehicle,” but
brake pads are better if your interest is specifically on the output of brakes. The painting
repaired category could use mixture of paint as the flow unit, but generally it makes more
sense to define the flow unit in terms of output rather than input. And while at Service
Advisor room, the service may more directly be concerned with the output of revenue in
terms of “$s.”

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Summarizing everything up, there are several critical rules with reference to determining
the flow unit:
1. Pick a flow unit up that relates to what you want to concentrate on and
measure with reference to the process.
2. Only follow the flow unit that you determined. Don’t measure some
aspects of the process using a customer as the flow unit and then switch to
vehicle. Combining things in distinctive units does not make any sense after all.
3. A selected flow unit that can be took advantage of describing and
measuring all the operations and activities within the process.

2.2.2. Three Key Process Metrics: Inventory, Flow Rate, and Flow Time
We can measure a process metric which can tell us about the capability of a process and
its performance. For a process examiner or creator, there are three main key process
metrics:

Inventory is the quantity of flow units which stay in a process. For example, “Toyota
vehicles” in process, “customers” in process, or “car’s genuine parts” in process.
Inventory is described as how much item is in the processing step. Overall inventory
occupies space and may charge a certain amount of money, and this is a good thing to
acknowledge in mind. For instance, if the normal inventory of Toyota cars in Toyota Bien
Hoa service rockets rapidly, then the company might eventually require a larger parking
space, which goes along with some extra charges. Besides, if a car component retailer
needs to boost the quantity of genuine parts and engine oil in the store, then the owner
might have to get a bigger store (which the rent is higher than the exist one) and more
cash needs to be available to purchase that inventory.

Flow Rate is the rate at which flow units go from the beginning to the end of a process.
As a rate, it is calculated in “flow units per unit of time”; for instance, “cars go to TBH
service per month”, “waiting time per customer”, or “Toyota Camry sales per year”. The
main factor of a rate is that it is often demonstrated in terms of several unit per unit of
time. If the “per unit of time” is not available, then it is just inventory only.

Flow Rate = Minimum {Demand, Process capacity}
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Flow Rate can illustrate how much item moves through the processing stage per unit of
time. More units traveling through a processing step is basically desirable because the
direction of the processing phase is all about yielding result.

Flow Time is the period a flow unit is dealt with in a processing stage, from the
beginning to the end. Certain units for this calculation are minutes, hours, days, weeks,
months, or years. Flow Time could demonstrate how much time that item spends in the
processing stage. If you are a customer in the Toyota Service Advisor room, then you
surely care about your Flow Time. The leader of the Service Advisor group is therefore
interested in Flow Time because it affects the customers’ satisfaction.
2.2.3. Little’s Law – Linking Process Metrics Together
Little’s Law is the law that can be explained as the connection between three main basic
key process metrics: Flow Rate, inventory, and Flow Time.
In any processing stage, the three main key process metrics are firmly connected to each
other in the following way, known as Little’s Law:
Inventory = Flow Rate × Flow Time
(Shorthand version: I = R × T)
Little’s Law is unusually effective, but it is also just basically simple. It informs us that if
we acknowledge any two out of three of the process metrics, we can surely take a guess,
or derive, the third. Moreover, if adjusting our process, we modify one of the metrics
while maintaining a second one unchanged, then we can find out how the third one
changes.
How about applying Little’s Law into the Express Maintenance process? Let’s just pick
up a simple data for example, the Flow Time is T = 2.06 hours and the Flow Rate is R =
1.08 cars/hour. Therefore, according to Little’s Law, the average inventory of vehicles
throughout the day is:
I = 1.08 cars/hour × 2.06 hours = 2.22 vehicles
The advanced potential of Little’s Law is that it could operate on any process. For
instance, we observe customers (our flow unit) loading onto the escalator in the shopping
mall in Vincom district 9, which is 150 feet (45 meters) long. It is a rush hour time of the
day and we clearly see that the Flow Rate of shoppers onto the escalator is 2.8 people per
second, R = 2.8 shoppers per second. We then hop on the escalator ourselves and record
that the Flow Time from bottom to top is 35 seconds, T = 35 seconds. While riding on the
escalator, we try to count the quantity of shoppers riding with us, which is the inventory

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metric for this process, but it is not easy to see everyone. Besides, there seem to be too
many customers to count. By using Little’s Law, we can determine the average inventory
of shoppers on the escalator:
Inventory = R × T
= 2.8 shoppers per second × 35 seconds
= 98 customers
2.2.4. Conclusion
In conclusion, Little’s Law, provides more examples of processes in which the three main
key process metrics can be connected to each other thanks to Little’s Law.
2.3. PROCESS ANALYSIS
2.3.1. How to draw a Process Flow Diagram
 Step 1: Summarizing all the stages you have in current service management.
 Step 2: Classifying processes. General processes which every input material
have to travel through. Special processes for materials require special
demand. For instance, Reception and Delivery sub-processes are the places
which all of input materials have to pass through. But for EM, GJ and BP are
repaired categories that only complete distinctive repaired orders of different
input materials.
 Step 3: Stimulating by using graphs or geometry, various colors and shapes
may also be used to demonstrate different tasks. Form the example above, we
use squares for GJ and circles for BP, so that they can be easily recognize,
and arrows illustrate direction of the workflows.
What is a Process Flow Diagram?
Process flow diagram is a type of graph which demonstrates your current service
operation in a detail way. It consists of several stages which input materials need to be
transform into serviced products at the output phase. With Process Flow Diagram, it will
assist some of the workflows for high-level managers:

- Have the general picture of service management.
- Easily spot the workflows and bottlenecks.
- Easily adjust and utilize processes in the future.
Application of Process Flow Diagram in Automotive Industry
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With the subject is automotive dealerships, process flow diagram illustrates step-by-step
carefully of a certain accidented vehicle will have expereinced from customer arrival to
important service repair is completed.
Below here is Process Flow Diagram at a certain automotive repaired service.

Figure 2.6 General Process Flow Diagram
From the Process Flow Diagram above, input materials will be distributed into 3
distinctive contents which include:
1. Reception has the responsibility of receiving and classifying customers.
2. General Jobs are responsible for all the tasks in the General Jobs repaired
service (General Jobs), for every quick maintenance (Express Maintenance),
or for tasks which related to painting (Body & Paint)
3. Delivery will receive input vehicle’s profile after accomplishing all the
services, and then guide customer to pay total receipt.
Observing the graph from above, high-level managers will have a clear picture of current
real-time workflows in their operation management. Which job positions take
responsibility for which tasks? If the overview is acknowledged, spotting bottlenecks in
processes will become way more recognizable thanks for simple measurements.
Process Analysis
It gives an exact foundation for acknowledging the closed-up operations of a company or
a business, insist of the solutions to the difficulties developed in the past segment.
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Process analysis opens the black box of the operations and peeks inside by determining
and analyzing all the activities related in serving one unit of demand or giving one unit of
supply. When the process has been analyzed, it can be improved: you can serve more
consumers, you can answer the correct quantity of employees to work for you, and you
can get your buyers what they really feel like in short amount of time. In brief, your
process can be enhanced and better.
Everyone who operating a business can use this framework which is known as process
analysis. Process analysis, for example, can be used by the person who owns the small
company, by those managing the Toyota Bien Hoa service, by those working in the
Toyota Bien Hoa service, or by those consulting to the company. In smaller car services,
this is the responsibility of the owner. In bigger services or service brands, many job
positions exist that consist of the term “operations” in it, like Operations Expert, Director
of Operations, Chief Operating Officer, Vice President of Operations, and many more.
But acknowledging the operations of a company is crucial to everyone. Overall,
everybody should have an interest in making it better in the business. By drawing a
process flow diagram is the ideal way to start any analysis of an operation. A process
flow diagram is a graphical way to tell the process. It will encourage us structure the data
and figures we collect as we try to develop our acknowledging of the process. By using
the case of Express Maintenance at Toyota Bien Hoa, we will demonstrate this new
material. We have the feeling that Express Maintenance provides an ideal example,
because we suppose that most of modern customers nowadays have been in car dealers or
vehicle garages, maybe even a large car service. At the aggregate level, the car repaired
service includes a quantity of customers, a set of employees, some work Sub-process, and
a Cash Register or Service Advisors.

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Figure 2.7 Activities at Reception sub-process of EM service

At Toyota Bien Hoa, there are some stages for Express Maintenance. The stages for
Express Maintenance service provide you with detailed instructions on how to make
quick repair on the vehicle. Figure 2.7 gives instructions on how to quick repair on the
certain vehicle depends on the vehicle’s odometer and customers’ need. We refer to the
steps shown in the table as activities. Several of the activities in Figure 2.7 relate directly
to repairing and fixing vehicle. But Figure 2.7 also consist of a set of activities that need
to occur when interacting with customers in Toyota Bien Hoa service, from greeting the
customer to ringing up the customer to pay the repaired order total bill. When meeting at
Service Advisor room, our customer is the unit of analysis – we refer to her or him as our
flow unit. We also label the quantity of customers in the process as inventory.

When a car purchaser arrives at Toyota Bien Hoa service, that person is politely
welcomed by the first employee and then guide to meet Service Advisor. The Service
Advisor has a duty of receiving the customer’s information, vehicle’s condition,
odometers and starting the repair order. We can consider the employee as a resource.
Resources assists the flow units travel from being an intake unit to transforming a result
unit. We use several directional arrows in a process flow diagram to illustrate the flow
unit’s trip from intake to result. In our scenario, the flow unit has just transported from
the waiting line (inventory) to the first resource. Resources are stimulated as rectangular
boxes in the process flow diagram. Then, our process flow diagram includes a set of a
triangle, a box, and an arrow.

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Following that, for instance, the first employee in Express Maintenance (employee A) has
finished the work, the second employee (employee B)’s turn is to replace old tires on the
vehicles and then install the new ones. Then employee B puts old tires into customer’s
car. The second employee has a duty of a different arrange of actions for the flow unit,
which is why we can draw a second box for employee B with an arrow going from the

first box to the second box. Depending on how fast employee A works relative to
employee B, we might see a line forming between the two basic sub-processes, which is
inventory. Next, we put a triangle between employee A and employee B to illustrate this
in the process flow diagram. Following employee B, employee C‘s duty is to offer the
consumer another repair service and receive total bill from repair order. We can observe
this time, we create a box to the process flow diagram, along with two more arrows and a
triangle between employee B and C. Now the consumer has a well-fixed vehicle and so
we finish the process flow diagram. The process flow diagram emphasizes a directional
flow in the process. Keep this in mind, we consider the start of the flow as the upstream
of the process and the result of the process as the downstream. We further see that a
resource upstream from another resource serves half-finished repaired car to the resource
downstream. Other saying, we can think about sub-process 2 being the consumer of subprocess 1.

Figure 2.8 Complete Process Flow Diagram
2.3.2. Capacity for a One-Step process
There are many actions and operations related to completing one consumer order, starting
with “welcome the customer” and ending with “ring on register.”

Processing Time – The period that one flow unit is accomplished by a resource.

Capacity – The maximum quantity of flow units that can travel from start to end of that
resource per unit of time.

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Process Capacity – The maximum Flow Rate a process can give per unit of time. This
defines the maximum provide of the process. The process capacity is the smallest
capacity of all resources in the processing stage.
Process Capacity = Min [Capacity[i]]

2.3.3. How to Compute Flow Rate, Utilization, and Cycle Time
Now, assume we have a demand rate of
Demand = 50 units/hour
The demand rate is the qunatity of flow units that consumers want per unit of time. So 50
consumers want a 3M paint protection film (3M PPF) each hour, but we only have the
ability to make 40. We next determine the Flow Rate as:
Flow Rate = Minimum{Demand, Process capacity}
= Minimum{50 consumers/hour, 40 consumers/hour}
= 40 consumers/hour
In this scenario, the feature which limiting the Flow Rate is the process capacity.
Therefore, the demand is more than supply and the Flow Rate is equal to process capacity
as capacity-constrained. If the process capacity is more than demand, the Flow Rate will
be equal to the demand rate and so we consider the process as demand-constrained.
Following that, we identify the utilization of a process as the ratio between the the
process capacity and the Flow Rate.:

Finally, we define the Cycle Time in a process as

Demand Rate – The quantity of flow units that consumers want per unit of time.
Flow Rate = Minimum{Demand, Process capacity}
Determine the capacity of a resource with X (for multiple) employees staffing that
resource as:

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With more capacity and more demand, our Flow Rate would go up to:
Flow Rate = Minimum{Demand, Process capacity}
= Minimum{200, 120} = 120 customer/hour

We can also compute our utilization as:
Utilization = Flow Rate/Capacity = 120/120 = 1
Our Cycle Time thus goes down to
Cycle Time = 1/Flow Rate = 0.00083 hour/customer = 30 seconds/customer
Even those experienced in operations, confuse the terms Cycle Time and lead time. We
determine the Cycle Time as 1/Flow Rate. Therefore, Cycle Time is demonstrated in units
of time per unit.
On the contrary, lead time is the period between a consumer placing individual’s order
and that order being completed. Lead time is identified as Flow Time, the time a flow
unit takes to travel through the process. Lead time are illustrated in units of time.
2.3.4. How to Analyze a Multistep Process and Locate the Bottleneck

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