CONCLUSION AND SUGGESTION MINIMIZING INVENTORY COST OF WELL SANITARY IN CV ROJO SOLO.

(1)

95 CHAPTER 6

CONCLUSION AND SUGGESTION

6.1. Conclusion

After all simulation and analysis process have

been arranged, there are several conclusions could be

made to control the inventory of Well Sanitary at CV

Rojo. The conclusions based on the result of simulation

are used to answer the objectives of this research,

they are:

1. The simulation which gives the best result is the

simulation with fixed order period and considering

the discount of delivery cost. The order will be

scheduled every four days, and the limit of order

quantity is 25 mixed items for each order period.

Schedules of order are 4 days period, but the order

decision depends on the reorder point (ROP). The

order quantity is calculated by subtracting TSL with

the number of stock.

When the order quantity is lower than 25 items,

there should be an additional order based on the

inventory ratio, the lowest will be chosen first.

The lower inventory ratio makes the greater demand

that possible to occur.

2. The ROP and TSL for the best scenario are shown in

table 6.1.

_____________________________________________________ Table 6.1. ROP and TSL for Best Scenario

type color ROP TSL

(2)

96

Table 6.1.(Continued) type color ROP TSL

8840 ivory 8 15

8840 blue 3 5

8840 beige 3 4

8840 pink 4 5

8840 grey 3 4

8840 black 5 10

8901 white 13 20

8901 ivory 6 10

8901 blue 3 9

8901 beige 3 6

8901 pink 3 6

8701 white 28 43

8701 ivory 14 20

8701 blue 2 3

8701 beige 3 6

8701 pink 3 6

8808 white 17 29

8808 ivory 10 17

8808 blue 3 6

8808 beige 3 5

8808 pink 2 4

9888 white 15 27

9888 ivory 13 18

3888 white 30 52

3888 ivory 13 16

b212 white 8 13

b212 ivory 4 5

[image:2.595.89.507.105.761.2]

(3)

97

Table 6.1.(Continued) type color ROP TSL

bu05 white 10 13

bu05 ivory 9 13

_____________________________________________________

3. The number of replication for the best scenario is 3

replications.

4. Total holding cost for Well Sanitary at CV Rojo on

real condition is Rp 9,839,790.96 and the best

simulation model result is Rp 6,311,704.11 in

average; so there is a decreasing cost as much as Rp

3,528,086.85 or 35.86%.

5. The stockless for Well Sanitary at CV Rojo on real

condition is 119 items during 2011, and based on the

result, the simulation reduces all the stockless as

much as 100%.

6. The total inventory cost for Well Sanitary at CV

Rojo on real condition is Rp 37,836,790.96 and the

average of total inventory cost on the best

simulation model is Rp 37,190,704.11; there is a

decreasing cost as much as Rp 646,086.85 or 1.71%.

6.2. Suggestion

In order to reach optimum inventory, CV Rojo needs

to improve their inventory management, including manage

the order schedules, ROP, and order quantity to reduce

stockless and overstock. Improved inventory management

is also needed to minimize the inventory cost.

Considering the limit of order quantity to get the

[image:3.595.91.513.113.590.2]

(4)

98

cost, however the additional order of products should

be noted. Doing continuous improvement on the ordering

policy by considering the discount aspect can be great

(5)

99 References

Fransisca, 2011, Analisis Pengendalian Persediaan Spare

Part Sepeda Motor Honda di PT Menara Agung, Thesis

of Industrial Engineering Program, Faculty of

Industrial Technology, Universitas Atma Jaya

Yogyakarta, Yogyakarta.

Heizer, J., Render, B., 2005, Operation Management,

Seventh Edition, Prentice Hall, New Jersey.

Law, M., Kelton W.D., 2000, Simulation Modeling and

Analysis, Third Edition, McGraw Hill, Singapore

Poernomo, H. Nugroho, 2011, Analisis Persediaan Produk

di UD Modern, Thesis of Industrial Engineering

Program, Faculty of Industrial Technology,

Universitas Atma Jaya Yogyakarta, Yogyakarta.

Richi, Thomas Maria, 2006, Analysis of Inventory System

Using Simulation (Case Study at PT. Ekadharma Tape

Industries), Thesis of International Industrial

Engineering Program, Faculty of Industrial

Technology, Universitas Atma Jaya Yogyakarta,

Yogyakarta.

Tersine, Richard J., 1994, Principles of Inventory and

Material Management, Fourth Edition, Prentice Hall

Inc., New Jersey.

Waters, C.D.J., 2003, Inventory Control and Management,

John Wiley & Sons, New York

Walpole, Myers, YE, 2002, Probability & Statistics: For

Engineers & Scientists, Seventh Edition, Prentice

Hall Inc., New Jersey.

Winata, Predian., 2009, Analisis Kebijakan Perencanaan

(6)

100

of Industrial Engineering Program, Faculty of

Industrial Technology, Universitas Atma Jaya

(7)

(8)

(9)

(10)

(11)

(12)

(13)

(14)

(15)

(16)

(17)

(18)

(19)

(20)

(21)

(22)

(23)

(24)

(25)

(26)

(27)

(28)

(29)

(30)

(31)

(32)

(33)

(34)

(35)

(36)

(37)

(38)

(39)

(40)

(41)

(42)

(43)

(44)

(45)

(46)

(47)

(48)

(49)

(50)

(51)

(52)

(53)

(54)

(55)

(56)

(57)

(58)

(59)

(60)

(61)

(62)

(63)

(64)

(65)

(66)

(67)

(68)

(69)

(70)

(71)

(72)

(73)

(74)

(75)

(76)

(77)

(78)

(79)

(80)

(81)

(82)

(83)

(84)

(85)

(86)

(87)

(88)

(89)

(90)

(91)

(92)

(93)

(94)

(95)

(96)

(97)

(98)

(99)

(100)

(101)

(102)