| Author | Soewandi, Hanijanto |
| Call Number | AIT Thesis no.IE-93-17 |
| Subject(s) | Inventory control
|
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of
Engineering, School of Engineering and Technology |
| Publisher | Asian Institute of Technology |
| Abstract | This study considers the problem of ordering and issuing policies for a two-stage
distribution system of fixed-lifetime perishable products that face stochastic demand with
known distributions. The parent inventory is first kept at stage I every cycle. Issuing quantity
is done to stage II every period. A cycle (n-period) lifetime at stage I and one-period lifetime
for sub-products at stage II are assumed. The decisions to be taken are the ordering quantity
from the outside supplier in a cycle and the quantities of the processed sub-products allocated
to the shelves in every fixed period. With these decision variables, the objective function
consists of revenue and cost from stage II as well as stage I. For stage II, the revenue comes
from selling quantity and salvages at the end of every period. The cost for stage II consists of
ordinary issueing (processing), holding, and emergency issue costs. For stage I, the revenue is
only the salvage value at the end of a cycle while the cost involved are ordering, holding, and
shortage costs. Mathematical model and simple approximation scheme are developed to tackle
the problem. Numerical experiments are also carried out in order to see the properties and
behaviors of the optimal solutions. This numerical experiments is also compare with the
simulation results for Poisson distribution. It seems that the approximations produce a very
good results, especially when the system does not experience runout for any sub-product.
Numerical experiments show that emergency issuing policy is fully utilized when the system
plan to have shortages for some sub-products. In general we cannot show the concavity of the
profit function. Furthermore, we also find that the approximated profit function has several
local points which depend on the runout period. But under the partial emergency issuing policy
( /3; policy), we can show that the profit function is jointly concave. Further observation should
be done to justify the use of this modified policy. |
| Year | 1993 |
| Type | Thesis |
| School | School of Engineering and Technology (SET) |
| Department | Other Field of Studies (No Department) |
| Academic Program/FoS | Industrial Engineering (IE) |
| Chairperson(s) | Fujiwara, Okitsugu
|
| Examination Committee(s) | Tang, John C.S. ;Nagarur, Nagendra N.
|
| Scholarship Donor(s) | Austria Government
|
| Degree | Thesis (M.Eng.) - Asian Institute of Technology, 1993 |