Class:DSES 6620 Simulation Modeling And Analysis

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Class DSES - 6620 Simulation Modeling And
Analysis Homework L3.4 Exercises Name Kevin
Lewelling Date February 6, 2002 1. For the
example in Section L3.1 (Fantastic Dan), run the
simulation model for a whole year (250 days, 8
hours each day) and answer the following
questions
A. On average, how many customers does Dan serve
each day? 52.784 customers B. What is
the average number of customers waiting to get a
haircut? 7.712 customers What is
the maximum? 10 customers C. What is
the average time spent by a customer in the
salon? 35.048 minutes What is the
maximum? 41.433 minutes D. How busy is
Dan on average? 99.97 Is it
Satisfactory? Youll have to ask
Dan. E. How many chairs should Dan have for
customers waiting for a haircut? The
max. quantity in the system is 10. Dan is
working on 1. Dan should therefore have 10-1
chairs available, or 9 chairs for his customers.
2. If Dan could take exactly nine minutes for
each haircut, will it improve the situation?
Rework Question 1 and answer parts A through E.
A. On average, how many customers does Dan serve
each day? 53 customers B. What is the
average number of customers waiting to get a
haircut? 7.524 customers What is
the maximum? 9 customers C. What is
the average time spent by a customer in the
salon? 35.223 minutes What is the
maximum? 39.725 minutes D. How busy is
Dan on average? 99.97 Is it
Satisfactory? Youll still have to ask
Dan. E. How many chairs should Dan have for
customers waiting for a haircut? The
max. quantity in the system is 9. Dan is working
on 1. Dan should therefore have 9-1 chairs
available, or 8 chairs for his customers.
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3. In theArrivals element (table), there are
these two items - occurrences and frequency.
What is the difference between the two? What is
the significance of the Qty each... column?
Occurrences defines the number of entities
that will be allowed to arrive in a system. The
Frequency of the arrival indicates how often an
entity will enter the system. The Qty each
column allows the user to enter the number of
entities that will arrive at the same time. 4.
What are the various time units that you can use
while developing a model? Where do you provide
this information. Time units can be
entered in seconds, minutes, hours and days.
They can be selected by going through the
Simulation pull-down menu and clicking on
Options. 5. The Processing element has two
tables that need to be edited. What are their
names and what are their functions?
The table names are Process and Rounting. The
Process table allows the user to define the
routing through the system as well as what
operations will take place for theentities at
each location. The Routing table allows the user
to specify the entity type and quantity resulting
from an operation at a location. 6. When an
entity has completed all the processing in the
system, what should we do with it? Where should
it be routed? We should tell the
system to allow the entity to exit the system.
It should routed out of the system to wherever it
is required next, maybe to be shipped. 7.
Differences between the following
A. Entity versus Locations. Entities
are the items that are processed in the system.
Locations are fixed places in the system where
entities are processed, queued, or have a
decision made about further routing. B. Locations
versus Variables. Variables are
typically used for making decisions or for
gathering data. Variables are implemented at
Locations. C. Attributes versus Variables
Attributes function as variables that are
specifically associated with individual locations
or entites. Variables may change during the
process however attributes remain fixed. D.
Subroutines versus Macros. A
subroutine is a user defined command that can be
called to perform logic and optionally return a
value. A macro acts like a subroutine however it
is different in that it cannot pass or return a
value. E. Table Functions versus Arrays.
Table functions provide ans easy and convenient
way to retrieve a value based on an argument that
is passed to the table. Arrays also provide as
way to retrieve data. Unlike a Table function,
data reference is based on location in the array,
not an argument. F. Save versus Save As.
Save saves the file with its existing file name
in its existing location. Save As allows the
user to change the name and the location of the
file.