8 - Systems Engineering Management

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SYSTEMS ENGINEERING

MOOC 8 – SYSTEMS ENGINEERING MANAGEMENT
PART 1
Systems engineering is not all about the process that
results in the design and development of a solution.
Systems engineers are also responsible for managing
the process to ensure that it remains focused and
delivers expected outcomes without exposing parties
to excessive risk.
In this session, I will look at some key systems
engineering management issues and explain why
they are important and what they achieve. I won’t
try to cover every conceivable element of
management but rather give you a good feel for the
types of management issues that arise.

I will look briefly at our interest in thoroughly and
progressively testing our systems before handing
them over to our stakeholders. The need for testing a
system prior to use is self-evident but what is
sometimes not so clear is the time, money and risks
associated with a comprehensive test program.
Unless it is managed properly, waste will result and
the testing program will fail to deliver the expected
results.
Managing the configuration of all of the elements of
our system can be tedious but if it is not done
properly, we will sentence the through life support
stakeholders to a life of pain and frustration as they
attempt to support a system whose configuration is
not known. Imagine trying to modify a complex
system when the system does not appear to be
accurately documented or when there seems to be
significant variation in configuration across a fleet of
systems that are meant to be identical.
Risk is essentially the chance of something
happening that adversely impacts on objectives. On a
technical system development, there are plenty of
risks that we face routinely. Should we use off the
shelf systems or or should we develop them from
first principles. Should we use an experienced team
of experts for the technical program or should be use
less experienced personnel. Maybe there are
technical risks that need to be addressed by the
design. For example, what is the severity of the risk
of an aircraft loosing electrical power to flight or
safety critical systems. How can we reduce those

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risks by designing redundancy into our design.
Technical risk management is the focus of a lot of the
things we do as systems engineers.
Speaking of risk, it makes no sense to “set and
forget” the design and development effort and only
check on it when it is meant to be completed.
Instead, we tend to look for periodic reviews of our
actual progress compared to planned progress. This
allows us to address issues, answer questions, clarity
conflicts, consider design decisions and record
rationales at discrete points in our process. It also
supports the desire of systems engineering to
address problems as soon as possible not as late a
possible. You will recall from an earlier module that
addressing problems as soon as they arise is the
most economically viable and time-effective
approach.
Another critical part of systems engineering
management that is strangely often overlooked is the
need for systems engineers to consider the unique
situation in which they find themselves. The process
we described in this MOOC is just an example of how
a program may be structured. The approach we
presented is often called the waterfall approach
because the whole system is developed in one pass;
starting at the system level at the top then cascading
down to the subsystem level and then finishing with
the component level, in that order. I have heard
some people say that the waterfall approach is
dangerous and never works. In my view, this is just
plain wrong. The waterfall approach can work, but it
doesn’t work all of the time. It relies on a thorough
and complete understanding of the problem and the
desired solution. It assumes the accurate translation
of this into comprehensive system level
requirements. It works best when these
requirements do not change very often. It assumes
that technology is available and works best when
that technology remains relatively stable over the
course of the system development. It assumes that
we have enough time and enough money to solve
the entire problem in one pass. A lot of assumptions,
aren’t there? Well, I have worked on projects where
all of these assumptions were valid and the waterfall
approach was employed with great effect, so to say it
is dangerous and never works is not correct in my
view. However, what I think those critics are probably
saying was that it is not common to come across a
situation where all of those assumptions are in place.
If any of those assumptions are not in place, then
systems engineers must think of alternative ways of
executing the systems engineering process. Forcing a
waterfall approach under unsatisfactory
circumstances will expose the program to risks such
as cost and time overruns (caused by potentially

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extensive rework) and delivery of a system that has
been based on invalid or out of date sets of
requirements. We will have a look at some
alternatives to the waterfall approach in this session,
but systems engineers must be capable of
independent thought in this area and not just follow
a process because that’s how it has always been
done.
Once we have listed all of these things that we need
to manage in systems engineering, it will come as no
surprise that we have some planning to do. We will
certainly produce a governing plan out of all of this,
but it is the planning process that is the valuable
exercise. The plan is just the artefact that results
from planning. The big thing to remember about
planning is that it needs to be ongoing in order to
keep up with the current situation.
Let’s now work our way through these areas and
cover some of the major themes.
PART2
Why do we test things? We need to verify that our
design and development effort has been successful
by confirming that our design approaches have
resulted in components, subsystems and eventually a
system that meets it specified requirements. This
helps identify areas where redesign might be
necessary. This sort of verification is sometimes
called Developmental Test and Evaluation. An
example of component testing might be to test
different types of concrete before deciding on what
concrete to use in critical areas like footings or slabs.
We would then test the concrete as it arrives on site
prior to it being poured into the excavations.
Although it would appear to be inconvenient and
may even upset some people, It is much easier and
cheaper to reject poor concrete before it is laid only
to discover structural problems after our house is
built requiring expensive and time-consuming
rectification action.

As the system passes through production and
construction, we need to verify the acceptability of
the system generally against our system level
requirements. This sort of verification is often called
Acceptance Test and Evaluation because the aim of
this verification is to allow the customer to formally
accept that the system meets its system-level
function and performance requirements. Acceptance
testing will be a finite period of time and will involve
both the customer and the contractor. In our house...

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...example, it is likely to be a period of “walking
around” the house and having the different key
elements of the house “ticked off”.
Once the system enters the utilisation stage, we
continue to evaluate the system. Generally, this sort
of evaluation aims to continually validate that the
system is solving the problems that created the need
in the first place.

Naturally, this sort of exercise involves the system
being employed in operational environments, being
used by end-users who are trained by our training
system, supported by our support system, and so on.
As we live in our house, there are bound to be things
about it that we don’t like. For example, we may find
out something about our house that was not
apparent during acceptance testing that means that
our house does not meet the specified requirements
in some area. In this case, we would probably have
some recourse against the contractor in the form of
latent defect clauses or warranty provisions in our
contract. We would use these provisions to have the
defect rectified. In other cases, there may just be
things about the house that we would have done
differently if we had our time again. These
experiences may raise issues that result in
modifications or upgrades to the system.
Modifications and upgrades are an opportunity to reinvigorate systems engineering as far as the system
goes as the upgrades may be considered a system in
their own right.
Verifying and validating the system in this way is a
risk mitigator because it allows us to confirm design
adequacy, detect problems early, confirm
rectification action and so on. In other words, it helps
protect us from ending up with a system that doesn’t
work the way it was intended to work. Leaving
testing until right at the end of the production
process is leaving things too late. Progressive
evaluation is the key.

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We mentioned examples of verification method in
early modules. For example, we spoke about using
tests, demonstrations, inspections and analyses to
perform verification. Programs to adequately
evaluate a system must be planned and managed. If
they are not planned and managed, there will be
serious ramification such as project cost and
schedule blow-outs and acceptance into service of a
poorly evaluated system. The sorts of things that
need consideration include specialised facilities and
test equipment, personnel availability and training,
approved evaluation procedures, availability of
necessary external systems for the evaluation
program and so on. If things are planned properly,
we will not have to repeat evaluation unnecessarily
either. This will also save time and money. The
bottom line is that evaluation is a critical part of
systems engineering and it must be planned and
managed from the earliest possible stage in the
systems engineering lifecycle.

In my experience, if this planning is not done you'll
be left with a couple of very undesirable choices to
make. Such as: do I blow the project cost and
schedule to ensure that the system is adequately
evaluated, or, do I deliver a system on time and
budget without thoroughly evaluating it.
These aren't good choices to have to make, so avoid
having to make them by planning the evaluation
process and allowing for it in your cost and schedule
estimates.

Configuration management is a very important part
of systems engineering. It is there to make sure that
we maintain control over the versions of all of the
different things within our system design. This
includes our documentation (such as specifications
and drawings) and the hardware, software and
interfaces that make up the design.
For example, it is critical in building our house that all
parties involved in the house project are running off
the same set of drawings and associated
descriptions. Imagine the difficulties that would be
caused if the customer, architect and builder all had
different versions of a document that listed the
windows to be installed in our house. This could
happen if changes had been made to the document
without all parties being involved in the change
process. Configuration management aims to avoid
this sort of problem by establishing and maintaining
control.

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There are four basic elements to configuration
management. Firstly, we identify everything that we
are going to place under control. In our house, this
will include the set of drawings, specifications and
other documents that will be used on the project.
Only those documents listed are authorised for use.
This will also include pieces of hardware and
software used in our project. For example, the make
and model of washing machine, oven, hotplate and
security sensors are all examples of things that are
likely to be specified and agreed upon. In terms of
software, it is possible that integrated entertainment
systems, security systems or automated watering
systems will make use of specific operating systems
and other software. It might be that the version of
software running on some of these computer-based
systems is also specified.
Once we have identified what we are controlling, we
need to be able to communicate that to all parties.
We do this by being able to communicate what the
current configuration baseline is for any part of the
system. For example, we would want to be able to
see what the current agreed configuration of kitchen
appliances is and how this has changed over time.
This is called status accounting in configuration
management.
Speaking of change, a critical element of
configuration management is the ability to be able to
manage change. Change is not bad in itself but
change without adequate control and visibility is
potentially disastrous. Imagine if the customer and
architect kept making changes to the configuration
baseline of the kitchen without involving the cabinet
maker and builder. Naturally, the cabinet maker and
builder will build the kitchen against their baseline
but the customer will expect the kitchen to be
delivered against their baseline. Change
management is all about being able to gather the
appropriate parties together and look at change
proposals. In this case, the customer, architect,
cabinet maker and builder would get together to
discuss the proposed change. The cost and schedule
impact of the change could be discussed and a
decision can be made about whether to make the
change or not. Either way, everyone is informed and
decisions are made based on accurate information
which is the aim of the change management process.
Finally, configuration management also involves
periodically auditing the process to make sure it is all
working properly. We check that everyone is using
the latest agreed documentation in performing their
work and we confirm that the materials being used
and the construction process being used is in...

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...accordance with the design documentation.
Hopefully, our audits will confirm that everything is
working well. Poor audit results indicate that there
may be something wrong with our configuration
management system. Poor audit results therefore
warrant investigation. For example, if our plumber is
using pipes that are different from what the drawings
specify, this could be caused by the plumber doing
the wrong thing or it could be caused by the plumber
working from the wrong drawings. The former
requires action against the plumber whilst the latter
requires tightening of our configuration management
process.
PART3
There are all sorts of risks facing projects including
schedule risk (the risks of delivering a project later
than expected) and cost risk (the risk of going over
budget). Systems engineering assists in the
management of an array of risks including schedule
and cost risk but it is technical risk that is a primary
focus of systems engineering. Technical risk could
include delivering a system that:
•is not up to the required standard in terms of its
function and performance,
•is not able to be maintained in accordance with the
support concept,
•Is not sufficiently reliable to carry out its intended
missions, or
•Is too expensive or difficult to produce in the
required quantities.
To understand individual risks and then to compare
different risks to one another, we need to look at all
of them to appreciate the likelihood of the risk
occurring and understand the nature of the resultant
impact. At one end of the spectrum, we may face
risks that are extremely likely to occur and will have
dire consequences on our objectives if they occur. At
the other end of the spectrum, we may face risks
that are very unlikely and will have only a small
impact on our objectives. The former are extreme
risks and the latter are insignificant risks. Naturally, in
between the different combinations of likelihoods
and consequences result in an array of risk severity
assessments.
Systems engineering is a discipline that continually
assists with risk management. For example:
•we conduct progressive design reviews as we pass
through the design phase to try to detect and correct
errors as early as possible,
•we conduct rolling evaluation programs and audits
as the system passes through design and
development and into construction and
production to ensure that we have come up with a...

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...properly documented design that works.
we are always considering alternatives and choosing
the most balanced design approach to our problems.

Sometimes we are confronted with risks that are so
severe that they need action. Classic responses to
severe technical risks are to avoid the risk (by taking
an alternative design approach) or to reduce the risk
by either reducing its likelihood and/or impact. Let’s
say that the land upon which we are building our
house is a sloped block. There may be a risk of
subsidence on the block that is deemed too high. To
avoid this risk, we could include a retaining wall in
our design concept or we could use excavation to
level the block. It should be noted that by avoiding
one risk (in this case subsidence) we are invariably
exposing ourselves to others. For example,
excavation allows us to avoid the subsidence risk but
the process might be very expensive and time
consuming, exposing up to cost and schedule risk.
Let’s look at an example of reducing rather than
avoiding risk. Our house design concept might
include a spiral staircase. Although compact and
pleasing to the eye, the probability of someone
falling down the spiral staircase might be deemed too
high by the house owners and a more traditional
staircase requested instead. There is still a risk that
someone will fall down the staircase but the
probability will be much reduced and the revised risk
severity might now be acceptable.
Other examples of risk management within our
house design might be to build spare capacity into
the house for future growth. For example, we might
reduce the risk of overloading our electrical system
by ensuring that each circuit is only carrying 50% of
its design capacity. This reduces the risk of
overloading our circuits and provides a platform for
future growth. Another design approach that we may
take is to build redundancy into our designs,
especially for safety or mission critical elements of
the design. For example, we may consider our
watering system for our garden to be critical. If our
watering system fails, we risk loosing very expensive
plants, lawns and gardens. Of course, we might be
relying on the garden for our food also. In this case,
we might design a watering system that uses the
house power under normal conditions but is also
backed up by a battery in the case of electrical
failure. Another risk mitigator is to use design
diversity in our systems. Design diversity is where we
use different design approaches in our design of
redundant systems so that something that causes
one approach to fail will not necessarily cause the
other approach to fail.

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Let’s look at another example of using the concept of
design redundancy and diversity to reduce technical
risk. Let’s say we are working on an aircraft system
and there is a computer system on-board the aircraft
that must not loose electrical power. It might be a
flight control computer for example. Engineers will
be tasked to design an electrical system to provide
electrical power to that flight control computer.
Initially, their design might involve driving a
generator from one of the engines to provide the
necessary power. Upon review, this design may be
viewed as an unacceptable risk because of
probability of generator failure may be too high and
impact on flight safety may be dire. In short, failed
generator = no electrical power = no computer =
plane crash.
So, the engineers revise their design and use concept
of redundancy by adding a second generator run off
the other engine as a backup. If the main generator
fails, the backup generator can take over.
Another review of the design reveals that there are
circumstances that could cause both generators to
fail. This circumstance is often called a common
mode of failure. Engineers may solve this by using
the concept of design diversity and add battery. The
performs the same function as the generators – it
provides electrical power - but it does this in a
different way by using chemical rather than
mechanical means.
By using design techniques like redundancy and
diversity, the engineers have addressed the technical
risk (in this case, the risk of loosing electrical power
to a critical computer). Note that they have not
reduced the impact of the risk (if the computer
looses power, the aircraft still crashes) but they have
reduced the probability of the computer loosing
power. Because risk severity is a function of both
probability and impact, they have reduced the risk
severity by reducing he probability of it occurring.
Spare capacity, redundancy and design diversity have
been incorporated in the design of many technical
systems around us in order to mitigate risks.
Examples include cars, transport systems, aircraft,
medical facility design and so on.

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Spare capacity and redundancy has been included in
the design of many technical systems around us in
order to mitigate risks. Examples include cars,
transport systems, aircraft, medical facility design
and so on.
Sometimes, though, we consider the risks that we
are facing and decide to take on risks because of the
potential benefits that may accrue as a result of
taking those risks. For example, making use of
leading-edge technology in our designs can be risky
due to the unknown nature of leading edge
technology. However, there may be major
advantages in terms of function and performance
associated with using leading edge technology. In
other words, sometimes the “risk=return” adage is
worth considering.

Throughout this MOOC, we have discussed the idea
of periodically reviewing our work at logical points in
the design and development process. This is an
effective way of detecting errors, conflicts or
problems with our design as early as possible. After
all, we know that the earlier we detect issues, the
easier and cheaper they are to rectify.
In this MOOC, we are suggesting reviewing things
after major transitions. For example, we spoke of a
system-level review called the System Design Review
when we have transitioned from stakeholder to
system-level requirements.
We also suggested a detailed review that we called
the Critical Design Review when the designers
believed that they had completed the detailed design
for our system.

10

Conducting reviews of this nature just make sense
and are not mysterious systems engineering
activities. They are simply technical meetings that are
conducted in a controlled and professional manner,
involving appropriate groups of people, that aim to
review work packages, approve plans for the next
stages, and resolve any problems that are facing the
development effort. When I say that the meetings
are conducted in a controlled and professional
manner, I am referring to standard meeting protocol
such as:
•an agenda for each review outlining what is going to
be covered, how long it is going to take and who is
leading the presentations;
•minutes to be taken and agreed prior to the
conclusion of the meeting; and
•an agreed chairperson(s) to maintain control over
the meeting.
These technical reviews must be held at the
appropriate time within the development program. If
they are held too early, the development effort will
not be sufficiently advanced for the review to be
meaningful. If they are held too late, we may miss
opportunities to rectify issues or problems in a timely
fashion. My over-whelming experience is that
reviews tend to be held too early rather than too
late. My experience is that people like to be seen to
be progressing on-schedule even if the technical
program is lagging. The attitude seems to be that the
technical program will “catch up” after the review. By
conducting reviews against the project schedule
(despite delays in the technical program) it gives the
impression that the project is on-schedule.
Conducting technical reviews too early in order to
artificially adhere to a project schedule is not
recommended. Fixing problems with the technical
program as early as possible in the systems
engineering process is recommended. There is a
great expression that applies here that bad news is
not like red wine. Bad news does not get better with
age. It is best to recognise problems as early as
possible rather than pushing them to later (where...

11

...they have invariably become much worse).
Systems engineering planning must take account of
the technical program and plan for these design
reviews. Design reviews take time, cost money and
will involve a number of different people. That’s why
planning for them is important. The number and
nature of technical reviews will be different for every
project so we must think about every project as a
unique undertaking when considering how to
conduct the reviews. A risky project using
developmental technology and involving large sums
of money will be reviewed more thoroughly than a
project at the other end of the spectrum.
PART4
A fundamental systems engineering management
task is to determine the most appropriate technical
strategy to use to take our stakeholders’ expectations
and turn them into a system that solves the
stakeholders’ problems.
In this MOOC, we have used a classic process known
sometimes as the waterfall approach to
development. We chose this approach for this MOOC
for a few reasons:
•it remains a popular approach to systems
engineering,
•It is logical and sequential making it ideal for
explaining the whole systems engineering process,
and
•Even if it is not used as the development approach,
it still represents the basic building blocks of other
popular approaches.

To recap how we explained systems engineering in
this MOOC, using the house as an example, you will
recall that we assumed that we were going to do the
whole house project in one, single pass. That is, we
were going to go from a complete conceptual design
to a complete physical design in one pass. In doing
this:
•First the system is understood via requirements
engineering
•Then all of the system elements are identified and
understood
•Then all of the elements that need designing are
designed, integrated and tested
•Then all of the elements are integrated to form the
system and it is tested
•Then the whole system goes through production

12

This strategy does work in certain circumstances. For
example when:
•We have enough time and money to do the whole
lot at once
•We understand our requirements at the system level
well enough to base the whole effort on those
requirements
•Our requirements are sufficiently stable that they
don’t keep changing (forcing expensive and time
consuming rework)
•Technology and expertise is sufficiently available and
stable to be able to solve the whole problem at once
Note that to be successful, all of these things need to
be in place. If one or two are missing, then the
waterfall approach may not be the best approach.
There are alternatives.

Let’s say that we understood all of our requirements
for our house and we had the technology and
expertise in place to design and build the house but
we did not have enough time or money to do the
whole project at once. How would we proceed?
Common sense would tell us that we would design
the whole house so that the design accounts for
everything we want but that we would implement
the design in a series of interconnected stages or
phases. In between the stages or phases, we would
be living in the house and saving up money for the
next phase. Because we had taken the subsequent
phases into account right at the start, phase 2 would
be able to build on phase 1, phase 3 would be able to
build on phase 2 and so on. In systems engineering,
we would call this an incremental approach.

13

What if we didn’t really understand all of our
requirements in a lot of detail. We were certain of
some requirements but not others. We might build
the house based on the requirements we understood
and build plenty of spare capacity into the design so
as to address our future needs when those future
needs become apparent. As we live in the house, we
develop our requirements for additional capability.
When we have enough time and money and we
understand our requirements a little better, we can
embark on an evolution of the original house. This
might be in the form of an extension or a
reconfiguration. Naturally, in this case, we will be
constrained by whatever form the house currently
takes. Because we didn’t have a thorough picture in
mind when we started (like we did with the
incremental approach or the waterfall approach) we
may need to evolve in a sub-optimal manner. We
might, for example, find ourselves saying “if only I
had realised that I would want to do this extension
when I was building the original house, I would
have….” You can fill in the rest of the sentence with
things like “built a stronger concrete slab” or “located
the storm water drain in a different place” and so on.
The bottom line is that there are many ways to
execute the systems engineering process. We have
discussed the waterfall approach in this MOOC and
also touched on alternatives such as incremental and
evolutionary approaches. When people say that
systems engineering has not worked on a project,
they are probably saying that an inappropriate
systems engineering approach was employed on the
project. Systems engineering is definitely not a one
size fits all process. What works in one situation
probably won’t work so well in other situations.
Systems engineering must be tailored to suit
different situations.

All of the preceding discussions should highlight the
critical importance of planning the overall systems
engineering effort. For example, in the preceding
discussions, we have explained that we really do
need to plan:
What strategy are we using
Who is doing what
When are the reviews happening
What design, development and production resources
are required
What are some of the big risks we are facing...

14

...What is our approach to key systems engineering
issues like T&E, configuration management and
requirements engineering?
In developing an idea of the answer to all of these
key questions, we will be going through a planning
process. When we have agreed on the answers and
written those answers down, we will have a plan. In
systems engineering, this plan is generally called the
Systems Engineering Management Plan or SEMP.
The critical thing to remember is that the plan is only
an artefact. It is the planning effort that is the most
vital component of producing the plan. I am
sometimes asked to help organisations to produce a
SEMP. Sometimes, the organisation is focused on
producing an artefact that complies with some
formatting and content requirement. Really, this is
missing the point. What they really need is to go
through the planning process and discuss how they
are going to tackle all of the elements of the systems
engineering process and then write the plan. I can
not stress enough that the planning process results in
the plan.
Another point to make is that the plan (SEMP) will
not remain static over a typical project so systems
engineers mush continue to plan and update their
strategies to meet the challenges of a changing
situation. This is a fact of life on a typical project.

Systems engineering rarely, if ever, exists in its own
right independent from other professional
disciplines. Bringing a solution to a complex problem
into existence will involve a lot of different disciplines
working together.
Systems engineers are closely related to the
discipline of project management. In some cases,
project managers will need input from systems
engineers to organise things like scope, cost and
schedule estimates. In some cases, systems
engineers will need assistance from project managers
in order to do their job. There is a very strong
correlation between the systems engineering effort
and the project management effort.
Systems engineering is a lifecycle discipline. At
various points in this MOOC, we have discussed
lifecycle concepts that require us to think about
maintenance and support, facilities, training,
personnel, disposal and so on. A critical technical
discipline known as Integrated Logistics Support is
focussed on influencing the design and development
of our system with through life support in mind....

15

... To that end, there is a very strong relationship
between systems engineering and integrated logistics
support. Both disciplines need to work closely
together in order to achieve a system that both
meets customer requirements but one that is also
supportable through its life.
On technical projects, the systems engineering effort
will be responsible for managing, directing,
controlling and supporting an array of classic
technical disciplines. The nature of these disciplines
will vary depending on the nature of the project and
system. For example, on our house, we will be
dealing with technical disciplines such as carpenters,
joiners, plumbers, electricians, bricklayers and so on.
On more complex systems like a modern aircraft, we
will be dealing with aerospace engineers, jet engine
specialists, materials specialists, electronic engineers,
software engineers and so on. Naturally ensuring
that all of these disciplines are working closely and
cooperatively together will be a major determinant
of success. This is a major role of the systems
engineering management.

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