Ketika saya mengampu mata kuliah permodelan sistem, di mana mata kuliah ini merupakan mata kuliah untuk mahasiswa tingkat 3, saya menugaskan mahasiswa untuk melakukan sebuah penelitian sederhana dengan menerapkan prinsip - prinsip ilmiah ke lapangan langsung. Saya juga menantang mereka untuk dapat mempresentasikan hasil penelitian mereka dengan tampilan slide yang tidak biasa dan menjemukan. Hingga akhirnya, inilah beberapa di antaranya. Bagaimana menurut Anda?
5. Biggest
Mall
in
West
Jakarta
Including
shopping
mall,
office
tower,
and
hotel
developed
by
Podomoro
Group
Biggest Mall
West Jakarta
Has reached
visitors each month
(source: marketing.co.id)
2.9
million
Shopping Mall
Office
Apartments & Hotels
PROBLEM DEFINITION
Can be reached by
Car
Motorcycle
Public transportation
CAR PARKING
MOTORCYCLE
PARKING
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7. PROBLEM DEFINITION
WHAT
PROBLEM DEFINITION
WHERE
WHEN
WHO
WHY
Queuing System
Central Park Mall
Saturday
Visitor of Central Park Mall
Massive number of visitors
PROBLEM STATEMENT
Massive number of visitors in Central Park mall on
weekend (especially on Saturday) led to queueing in the
system. If queue happens more than 1 minute and time for
motorcycle to search parking more than 2 minutes, it will
decrease customer satisfaction so that it will cause
opportunity loss to Central Park Mall.
11. SOURCE OF DATA
Credible Expert
Opinion
Personal Observation
COLLECTION OF DATA
Queuing time
DATA GATHERING
Peak hour Capacity Searching time Arrival Time
Service Time Counter Duration of parking
P
1 2
13. RAW DATA & PROCESSING
DATA GATHERING
Capacity
(492) in Basement 1
(603) in Basement 2
14. RAW DATA & PROCESSING
DATA GATHERING
Searching time
Lantai 1
Mean 41.97
Std. 18.559
15. RAW DATA & PROCESSING
DATA GATHERING
Searching time
Lantai 2
Mean 81.1
Std. 15.7
16. RAW DATA & PROCESSING
DATA GATHERING
Duration of parking
0
5
10
15
20
25
30
35
40
30 60 90 120 150 180 210 240 270 300 330 390 420
Frequency
Minutes
Duration
of
Parking
Time
Mean
Std.
17. RAW DATA & PROCESSING
DATA GATHERING
Queuing timeArrival Time Service Time Counter
Observer 2
(observe the server)
Observer 1
(observer arrival)
Interarrival
rate
Arrival Time
Service
time
Arrival time in
server
18. RAW DATA & PROCESSING
DATA GATHERING
Queuing timeArrival Time Service Time Counter
Kedatang
an Ke-
Inter
Arrival Waktu kedatangan Server Waktu sampai depan loket
Service
Time Waktu keluar loket
Waktu
Antrian Antrian/Tidak
Detik Jam Menit Detik Jam Menit Detik Detik Jam Menit Detik Detik
1 3 13 10 3 1 13 10 4 5 13 10 9 1 Tidak antri
2 9 13 10 12 1 13 10 13 4 13 10 17 1 Tidak antri
3 1 13 10 13 1 13 10 18 6 13 10 24 5 Antri
4 23 13 10 36 1 13 10 37 5 13 10 42 1 Tidak antri
5 34 13 11 10 1 13 11 12 8 13 11 20 2 Tidak antri
6 12 13 11 22 2 13 11 23 4 13 11 27 1 Tidak antri
7 20 13 11 42 1 13 11 43 6 13 11 49 1 Tidak antri
8 15 13 11 57 1 13 11 58 9 13 12 7 1 Tidak antri
9 21 13 12 18 1 13 12 19 10 13 12 29 1 Tidak antri
10 18 13 12 36 1 13 12 37 4 13 12 41 1 Tidak antri
11 13 13 12 49 1 13 12 50 5 13 12 55 1 Tidak antri
12 18 13 13 7 1 13 13 8 8 13 13 16 1 Tidak antri
13 6 13 13 13 1 13 13 15 4 13 13 19 2 Tidak antri
14 8 13 13 21 1 13 13 22 17 13 13 39 1 Tidak antri
15 9 13 13 30 1 13 13 41 9 13 13 50 11 Antri
16 5 13 13 35 2 13 13 50 4 13 13 54 15 Antri
17 15 13 13 50 1 13 13 52 5 13 13 57 2 Tidak antri
18 13 13 14 3 1 13 14 4 6 13 14 10 1 Tidak antri
19 3 13 14 6 2 13 14 8 5 13 14 13 2 Tidak antri
20 6 13 14 12 1 13 14 13 7 13 14 20 1 Tidak antri
19. RAW DATA & PROCESSING
DATA GATHERING
Arrival Rate
20. RAW DATA & PROCESSING
DATA GATHERING
Inter-Arrival Time
21. RAW DATA & PROCESSING
DATA GATHERING
Service Time Counter 1
22. RAW DATA & PROCESSING
DATA GATHERING
Queuing time
2.899
1.555
2.578 2.679 2.851
1.752
0
1
2
3
4
13.10-‐14.09 14.10.15.09 15.10-‐16.09 16.10-‐17.09 17.10-‐18.09 18.09-‐19.09
Average
of
Queuing
Time
34. COMPARING WITH SPREADSHEET MODEL
VALIDATION
Spreadsheet Model
Pro
Model
Average server utilization (ρ) 0.2875 0.24
Average number of
customers in the queue (Lq)
0.0518 0.14
Average number of
customers in the system (Ls)
0.6268 0.61
Average waiting time in the
queue (Wq)
0.0002 0.018021 (minutes) 0.03
Average time in system (Ws) 0.0018 0.218021 (minutes) 0.22
Probability (% of time)
system is empty (P0)
55% 85%
Arrival rate during peak
time 345
motorcycle/hour
Average service time
during peak time 6
seconds
OBSERVATION
Saturday, 26-09-2015
11.10 am to 9.20 pm
268
259
289
383
268268
35. COMPARING WITH ACTUAL SYSTEM
VALIDATION
Visitors will first fulfill parking area block
which near the mall entrance
Visitors will only go to P2 if only P1
capacity is full. P2 will be open when P1
capacity almost full
Visitors tend to take Server 1 rather than
Server 2 (First Available)
If visitors didn’t find parking at P2, they will
look again the available area at P1
Actual Model
How? We create dummy process from P2
to P1 for motorcycle who didn’t get
parking at P2
47. OUTPUT ANALYSIS
OUTPUT ANALYSIS
WHAT TO WATCH?
Incoming/Outcoming Entities
Average time in queue (Wq) and in system (Ws)
Average number of entities in queue (Lq) and in system (Ls)
Utilization of queueing system
52. Wq = 0.03 min
Ws for Server 1 = 0.12 min
Ws for Server 2 = 0.13 min
They are within limits required from this assignment (1 min)
Therefor no additional server is needed for now
VERIFICATIONOUTPUT ANALYSIS
Average Time in Queue and Ticketing System
Lq = 0.15 entities
Ls for Server 1 & 2 = 0.62 entities
These number are similar with our Spreadsheet model
Average Number of Entities in Queue and System
53. VERIFICATIONOUTPUT ANALYSIS
Utilization of Queueing System
Server 1 utilization = 33%
Server 2 utilization = 14%
Their average are similar with our spreadsheet model
The server is under utilized even at peak time
Entity Activity
Average Time in system = 92.86 min
Average time in waiting = 0.03 min
Average time blocked = 0.92 min
Entity
Activity
Operation Waiting
Blocked
54. VERIFICATIONOUTPUT ANALYSIS
Utilization of Parking Space
Average time to search parking space
16 out of our parking space are utilized, 8 are continuously empty
Average of empty parking space = 31.8%
Average of full parking space = 28%
Average # of entities in parking space system = 432 unit per hour
There are overcapacity in Central Park parking system
Average time = 1.69 min
There are 6 locations where searching for parking space takes longer
than 2 minutes (B1 area 2, 4, 5, and 6). We aim to reduce that to less
than 2 minutes.
There are several options: increasing parking space, better routing and
capacity management
56. CONCLUSION
CONCLUSION
Peak time in Central Park
happens on
Saturday
at
13.10-20.20
Average
arrival rate in
Central Park is
345
motorcycles/
hour
Average
service time on
server 1 is 5,7 s
and on
server 2 is 5,8 s
Queueing time in lockets is
under 1 minute
and
searching time average is
under 2 minutes,
So, the parking system on
Central Park is optimal.
The problem that happens in Central
Park is mostly because of
breakdown in server.
So, queue only happen when the
server is breakdown.
58. RECOMENDATION
RECOMENDATION
The problem that happens in Central
Park is mostly because of
breakdown in server.
So, queue only happen when the
server is breakdown.
Better maintanance program for each server machine
Increase parking space
Better routing and capacity management
59. RECOMENDATION
RECOMENDATION
Increasing Parking Space
Basement 1 location 2 = From 10 to 50 parking spaces
Basement 1 location 4 = From 38 to 45 parking spaces
Basement 1 location 6 = From 38 to 50 parking spaces
Total Increase of parking space = 62
Average time to search parking space = 1.16 min
No more spending over 2 minutes to
search a parking space!
Constraint : Limited Space to Expand
60. RECOMENDATION
RECOMENDATION
Better Routing and
Capacity Management
Since there are 8 parking location that is continuously
empty, managementcan start routing entities there,
when queue start to form
Management can also partly closed several parking
locations on B1 to route entities to search for parking
space at B2