Thesis (MComm)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: FoodBank South Africa is an non-profit organisation formed to establish a national network of
community foodbanks in urban and rural areas of South Africa, with all participants working
towards the common goal of eliminating hunger and food insecurity. FoodBank Cape Town
was the first of these community foodbanks launched in South Africa on 2 March 2009. The
operations of FoodBank Cape Town include sourcing food and redistributing it to agencies
(social services organisations running feeding programmes). Currently the majority of the food
is sourced from the retail sector and then redistributed to approximately two hundred agencies.
The logistics involved in both sourcing and distributing food are vital to the efficient functioning
of FoodBank Cape Town. Since the costs associated with these logistics operations are very high,
streamlining these operations has been identified as a priority area for efficiency improvement.
The focus in this thesis is on the distribution logistics involved, specifically focussing on a facility
location problem according to which FoodBank Cape Town can establish local distribution depots
to which it delivers food and from which the agencies collect food assigned to them.
A mixed-integer programming model is formulated for the above facility location problem and
small test instances of the problem are solved using different exact and approximate solution
methods in order to identify a suitable solution methodology for the full (large-scale) FoodBank
Cape Town facility location problem. The full facility location problem is solved approximately
by means of a meta-heuristic solution method in the more highly constrained instances, while
an exact method is selected for solving the lesser constrained instances. The problem is first
solved based on the distances between the warehouse and the depots as well as the distances
between the agencies and the depots, for the twenty four instances where 17 to 40 depots are
located. The model is then developed further to incorporate the cost of distribution. This
cost-based facility location model is solved with a view to minimise the cost of food distribution
from the warehouse to the depots and the cost of food distribution incurred by each agency
to collect food from its assigned depot. A basic vehicle routing technique is applied to the
cost-based facility location solution and the associated costs of the distribution are updated.
This cost-based solution updating process is performed iteratively until the solution converges.
Since the cost of food distribution depends on the vehicle fleet composition used, a vehicle fleet
composition comparison of possible FoodBank Cape Town vehicles is performed to determine
the most desirable vehicle fleet composition to be used for the distribution of food to depots.
The results of the FoodBank Cape Town facility location problem and vehicle fleet composition
comparison are presented and recommendations are made to FoodBank Cape Town regarding
the preferred number of depots, the location of these depots and the preferred vehicle fleet
composition. / AFRIKAANSE OPSOMMING: FoodBank South Africa is ’n nie-winsgewende organisasie wat ten doel het om ’n nasionale
netwerk van gemeenskapsvoedselbanke in stedelike en landelike gebiede van Suid-Afrika op die
been te bring, waarin al die deelnemers die gemeenskaplike doel nastreef om honger en voedselonsekerheid
te elimineer. Foodbank Cape Town was die eerste van hierdie gemeenskapsvoedselbanke
in Suid-Afrika en is op 2 Maart 2009 gestig. Die take van Foodbank Cape Town sluit
in die versameling van voedsel en die verspreiding daarvan aan agentskappe (gemeenskapsorganisasies
wat voedingsprogramme bestuur). Die oorgrote meerderheid voedsel is tans uit die
kleinhandelsektor afkomstig en word aan ongeveer tweehonderd agentskappe versprei.
Die logistiek wat met hierdie versamelings- en verspreidingsprosesse gepaard gaan, is sentraal tot
die doeltreffende funksionering van FoodBank Cape Town. Aangesien die kostes verbonde aan
hierdie logistieke prosesse baie hoog is, is hierdie aktiwiteite as ’n prioriteitsarea vir verbetering
geidentifiseer. Die fokus in hierdie tesis val op die logistiek verbonde aan die verspreiding van
voedsel deur FoodBank Cape Town, en meer spesifiek op die probleem van die plasing van ’n
aantal lokale verspreidingsdepots waar FoodBank Cape Town voedsel kan aflewer en waar die
agentskappe dan voedsel wat aan hulle toegeken is, kan gaan afhaal.
’n Gemengde heeltallige-programmeringsmodel word vir die bogenoemde plasingsprobleem geformuleer
en klein gevalle van die model word deur middel van beide eksakte en benadere oplossingstegnieke
opgelos om sodoende ’n geskikte oplossingsmetode vir die volle (grootskaalse) Food-
Bank Cape Town plasingsmodel te identifiseer. Die volle plasingsmodel word aan die hand
van ’n metaheuristiese oplossingstegniek benaderd opgelos vir hoogsbeperkte gevalle van die
model, terwyl minder beperkte gevalle van die model eksak opgelos word. Die plasingsmodel
word eers met die oog op die minimering van afstande tussen die pakhuis en verspreidingsdepots
sowel as tussen die verspreidingsdepots en agentskappe vir die vier-en-twintig gevalle van
die plasing van 17 tot 40 verspreidingsdepots opgelos. Die model word dan verder ontwikkel
om ook die koste van die verspreiding van voedsel in ag te neem. Die koste-gebaseerde plasingsmodel
word opgelos met die doel om die voedselbankkoste van voedselverspreiding vanaf
die pakhuis na die lokale verspreidingsdepots sowel as die agentskapkoste van die afhaal van
voedsel vanaf verspreidingsdepots te minimeer. ’n Basiese voertuigroeteringstegniek word op
die koste-gebaseerde plasingsmodel toegepas en die verspreidingskoste word dienooreenkomstig
aangepas. Hierdie aanpassingsproses van die koste-gebaseerde oplossing word herhaal totdat die
oplossing konvergeer. Aangesien die koste van voedselverspreiding afhang van die voertuigvlootsamestelling,
word ’n vergelyking tussen moontlike vlootsamestellings vir FoodBank Cape Town
getref om die mees geskikte samestelling van voertuie vir die verspreiding van voedsel te vind.
Die resultate van die FoodBank Cape Town verspreidingsdepot-plasingsprobleem en vlootsamestellingsvergelyking
word aangebied en ’n aanbeveling word aan FoodBank Cape Town gemaak
in terme van ’n geskikte aantal verspreidingsdepots, waar hierdie depots geleë behoort te wees,
en ’n geskikte voertuigvlootsamestelling vir die verspreiding van voedsel.
| Identifer | oai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:sun/oai:scholar.sun.ac.za:10019.1/79860 |
| Date | 03 1900 |
| Creators | Lanz, Ernest John |
| Contributors | Van Vuuren, J. H., Stellenbosch University. Faculty of Economic and Management Sciences. Dept. of Logistics. |
| Publisher | Stellenbosch : Stellenbosch University |
| Source Sets | South African National ETD Portal |
| Language | en_ZA |
| Detected Language | Unknown |
| Type | Thesis |
| Format | 91 p. : ill. |
| Rights | Stellenbosch University |
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