Doctoral Degrees (Logistics)

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Advanced supply chain planning processes and decision support systems for large-scale petrochemical companies
(Stellenbosch : University of Stellenbosch, 2006-12) Louw, Johannes Jacobus; Pienaar, W. J.; University of Stellenbosch. Faculty of Economic and Management Sciences. Dept. of Logistics.
Conventional supply chain integration concepts focus primarily on the internal and external integration of individual supply chains (can be viewed as intra-supply chain integration). Due to the highly integrated nature of petrochemical value chains, related supply chains should also be integrated by taking account of enterprise/industry-wide synergies and interdependencies (can be viewed as inter-supply chain integration). Inter-supply chain integration can typically develop along three dimensions: - Upstream feed clusters (upstream in the chemical value chain) - Downstream product clusters (downstream in the chemical value chain) - Macro logistics network clusters (within and across related logistics networks for liquid bulk, dry bulk, packaged goods and gases) This dissertation presents a generic framework of applicable intra- and inter-supply chain planning processes that supports related long- (strategic), medium- (tactical) and short-term (operational) supply chain decisions for large-scale petrochemical companies. This type of companies has to manage relative complex supply chains. Highly complex supply chains (due to an extensive product portfolio, supplier base, customer base, manufacturing processes, transportation, and management processes and systems) require far more advanced planning processes than simple supply chains. Advanced supply chain planning processes cover an extended supply chain scope, deal with longer time horizons, and utilize more sophisticated analytical techniques and decision support systems. An extensive literature study, supplemented by empirical research in the South African petrochemical industry, provided the foundation for the advanced supply chain planning framework concluded in this dissertation. Semi-structured interviews and a questionnaire presented to an informed audience constitute the empirical research conducted. The related best practices, concepts, approaches followed, and level of advancement in three supply chain planning dimensions were derived. To guide petrochemical companies along the planning advancement journey, the roadmap developed can be utilized for the application and implementation of the advanced supply chain planning framework. This roadmap articulates the advancement stages, dimensions, characteristics, and triggers to advance. Typical characteristics associated with the advancement stages and dimensions provide the means for a company to assess their level of progression. The essential mechanisms that can enable interventions are also articulated.
The design principles and success factors for the operation of cross dock facilities in grocery and retail supply chains
(Stellenbosch : Stellenbosch University, 2004-12) Vogt, John Joseph; Pienaar, W. J.; Stellenbosch University. Faculty of Economic and Management Sciences. Dept. of Logistics.
ENGLISH ABSTRACT: The dissertation reflects the research done on the design principles and success factors for the operation of cross dock facilities in grocery and retail supply chains. The cross dock is a particular facility in the supply chain where goods are received from suppliers, sorted without storage of the goods, and then efficiently moved to downstream customers. Cross docks are not a new operation. However, the use in high volume grocery and retail operational capabilities is poorly understood and is not uniquely defined. The problem is that cross docks are often seen as extensions of warehouses. The same personnel, systems and processes are applied and the efficiency potential of the cross dock is not achieved. Warehouses are orientated towards storing the full range of product and allowing the pick to be done from this storage buffer to provide any or all of these products to a customer. Cross docks will only handle products that are used in larger quantities and that are sent to most, if not all, the customers. The cross dock is therefore distinct and very different from the traditional warehouse. The published research tends to focus on the technical aspects of the cross dock layout. This research is primarily in the scheduling of the trucks into the yard of the facility; the allocation of trucks to specific doors of the facility; and the allocation of doors to receiving and despatch functions within the facility. Very little information or research reflects the design principles and success factors for the cross dock and its supply chain. The only classification of the cross dock in the literature is whether the barcode is added to the item before or after receipt at the cross dock. For this research work a literature survey was conducted and five major operations were reviewed, in South Africa and the USA. The research empirically drew logical conclusions, which were tested in the operations and found to be correct. This allowed the design principles and success factors to be determined for a successful cross dock. The research extends the knowledge of the cross dock operation and design: - • A new classification for the feasible types of cross docks in the supply chain was developed. Three factors are shown to be of primary importance: - o Where in the supply chain the identification of specific items for a customer is done; o Where the sort is done for the items to be delivered to a customer; and o Whether the supplier is providing one product or multiple products to the sort. From these three factors, eight potential classifications could be defined. However, only three practical types of cross dock can be determined from these eight alternatives. These are named in this research as Cross Dock Managed Load (CML); Joint Managed Load (JML); and the Supplier Managed Load (SML). The cross dock is far more effective than the warehouse when the total work (excluding inventory) is considered. The earlier in the supply chain the product is identified for the use of the entire downstream supply chain, the more effective will be the total supply chain. Thus the greatest supply chain effectiveness possible is with the SML, then the JML and finally the CML. • The operation of a cross dock is very similar to a continuous manufacturing process. There is no buffer of stock to decouple the inbound and outbound processes, and the operation takes place in a restricted area. However, in the retail chain, the workload alters with different orders and different days. Daily load differences vary by as much as 90%. This results in vastly different workloads and variations of throughput. This is similar to a batch operation with highly variable workloads between batches. The literature recommends the use of Just in Time (JIT) practice for cross docks. This is inappropriate as its primary requirements are continuous full volume operation and continuous small improvements to achieve a balanced operation. The most appropriate method of process improvement is the Theory of Constraints (TO C) and not JlT. • The management must have a detailed, disciplined approach. This implies standardised methods of operation, and a high degree of training. Equally there is the requirement for a special type of personnel to operate the cross dock. These operating personnel must be able to operate with precision (i.e. very low error rates) and be able to maintain this capability for continuous periods. • The systems required for a successful operation must include the capabilities of Yard Management, WMS for cross docking, Order Management with Advanced Shipping Notice (ASN) capability and Track and Trace across the supply chain. The items need to be identified by a barcode. The information required on the barcode will be determined by. the information systems capability of the least advanced service provider in the supply chain. If this service provider can receive and transmit all the data required for the supply chain from and to the other members, then the barcode need only be an identification number of the specific item. The data pertaining to the items is then passed from system to system in the supply chain. If data movement is not possible between all the parties in the entire supply chain, then the barcode must contain the information that will identify the item, the origin and the final delivery destination. If the items are delivered as part of a consignment, a further quantum of information is required to identify the total number of items in the consignment and the specific item within the consignment. • The research shows that the overall capability of the cross dock or its maximum capacity is the combination of the capability of the personnel and the cross dock design. Restrictions on either the personnel capability or the design of the cross dock, or both, severely reduces the effectiveness of the cross dock. • The previous research on the sequence of allocation of trucks to specific doors within the cross dock can be enhanced with a new sequencing method. The new method allocates the transport, in sequence of arrival, to the open door that either numrruses the walk distance in the facility; or maximises the completion of the consignments in order to minimise the area required to build the consignments; or a combination of both. The choice of these will be determined by the constraints imposed by the design of the building. This is an important extension as this ties the supply chain into the cross dock operation, rather than looking at the cross dock in isolation as has been done in this previous research. • The factors that influence the design of a cross dock as to its size, shape, number of doors, and the specifically required additional areas, is defined in detail. The principles of these factors and their inter-relationships and dependencies are used in a detailed design for a cross dock. The detailed design process is set out from data analysis through to the actual size calculations and layouts. Measurements of walk distance and sort movement are used to determine the most effective design. The design is shown to be considerably more effective than the older designs. This work has significantly extended the research on the design principles and success factors for implementation of cross docks in retail supply chains. The research derives a unique new classification for cross docks. An improvement is made to existing research on the allocation of the transport to particular doors in the cross dock. The operation, management and personnel are shown to require specific characteristics. The information systems required for effective cross docks is determined and defined. The identification of the individual items by barcode and the information required within the barcode depending on the information sophistication of the service providers in the supply chain is defined. A detail process to design a cross dock is evolved, with the full knowledge of the factors that must be considered and their interrelationships. Measurements to determine the effectiveness of the design are used to choose the most appropriate design. All these are then synthesised into a new design, which is far more effective than any of the other designs researched. The design process will produce a very effective cross dock as has been demonstrated with a new facility.
'n Gerekenariseerde logistieke bedryfstelsel vir klein tot mediumgrootte sakeondernemings
(Stellenbosch : Stellenbosch University, 2004-04) Loubser, Jacobus Stephanus; Pienaar, W. J.; Stellenbosch University. Faculty of Economic and Management Sciences. Dept. of Logistics.
ENGLISH ABSTRACT: The logistical approach of ERF (Enterprise Resource Planning) software has certain shortcomings with respect to application in small to medium sized enterprises (SMEs) in South Africa. During the course of this study these shortcomings are identified, effective solutions are suggested and a logistical ERF program is provided. This ERF program is aimed at SMEs where stock items are handled, produced and shipped. SMEs experience problems with ERF systems, such as a high total cost of ownership, high complexities and the nature of the systems' design. The cost of international ERF systems is usually determined by stronger international currencies, creating price fluctuations and placing it outside the reach of SMEs. These systems generally comprise of a series of complex functions, of which only a limited quantity applies to local enterprises and logistics. Several configuration steps have to be completed before the advanced logistical functions may be used. ERF systems do not necessarily focus on logistics, but are made up of a combination of finance and other modules. Futhermore, the layout and design of the systems are aimed at a high-level user, which prevent the entry-level user from completing the logistical function with ease. The developed ERF program can be obtained and implemented at a low cost due to the standard base program upon which it lives, as well as the simple nature of the screens and menus. The program provides a logistical focus, with a simple path to electronic logistical functions. The design and supporting material for configuration and execution of the program provide the opportunity to an entry-level user to make use of the program effectively. This decreases the cost of implementing and maintaining the system, thus reducing total cost of ownership.
The measurement of supply chain efficiency : theoretical considerations and practical criteria
(Stellenbosch : University of Stellenbosch, 2010-03) Goedhals-Gerber, Leila Louise; Pienaar, W. J.; University of Stellenbosch. Faculty of Economic and Management Sciences. Dept. of Logistics.
ENGLISH SUMMARY: In an effort to compete globally, South African supply chains must achieve and maintain a competitive advantage. One way of achieving this is by ensuring that South African supply chains are as efficient as possible. Consequently, steps must be taken to evaluate the efficiency levels of South African supply chains. This dissertation develops the composite supply chain efficiency model using variables specifically identified as problem areas experienced by South African supply chains. The composite supply chain efficiency model evaluates the overall efficiency of a supply chain based on three criteria, namely, reliability efficiency, cost efficiency and speed efficiency. It identifies bottlenecks along the supply chain and in so doing identifies key focus areas for firms if they want to improve their overall efficiency and become more competitive. 3
A model to forecast the impact of road accessibility on the economic development potential of industrial land in urban areas
(Stellenbosch : Stellenbosch University, 2003) Botes, Francois Jacobus; Pienaar, W. J.; Stellenbosch University. Faculty of Economic and Management Sciences. Dept. of Logistics.
ENGLISH ABSTRACT: The dissertation firstly outlines the findings of recent studies that have recorded the relationship between transport and economic development. This includes the assessment of a number of economic evaluation techniques that are available to predict the impact of improvements in transport on economic development. An historic overview is provided of the role that transport has played in the development of Cape Town. Due to the fact that the phases of development followed international development trends, it is concluded that development in Cape Town will follow the global trend. A number of economic growth scenarios are developed for Cape Town to assess how the City will be able to cope with the socio-demographic challenges facing it in the next century. The relationship between land price and the economic development potential of land is outlined, as are the factors that determine industrial land price, namely the demand and supply of industrial land. The process of determining the economic value of industrial land is described. This includes the collection and analysis of occupation rent of industrial townships in Cape Town, the calculation of property values and the calculation of the shadow price of land. A procedure of determining accessibility to industrial townships in Cape Town was developed. Firstly, accessibility was defined in broad terms. This was followed by a discussion of each of the elements of accessibility namely proximity, access and mobility in order to understand the factors that may impact on the level of accessibility. Finally, the level of accessibility is quantified in terms of generalised cost. A regression analysis was undertaken to establish a statistical relationship between the economic value of industrial land and accessibility to the industrial townships. The development of a numerical model was based on the regression analyses to forecast changes in industrial land price given a change in accessibility. The model was then tested on a case study. The main conclusions of the study are as follows: (a) The accessibility of industrial land in Cape Town is linked closely to its CSD I Port (it was not possible to separate the CSD and the port), which is typical of a monocentric city structure. (b) There is a positive, significant, quantifiable relationship between accessibility as quantified by means of generalised cost and the economic value of industrial land, which was calculated by means of the shadow price technique. (c) There are a number of conditions that should be met for an increase in local industrial production potential to be translated into an equal amount of economic output.
Resilience as an imperative in public transport organizations
(Stellenbosch : University of Stellenbosch, 2011-12) Proper, Jan Willem; Pienaar, W. J.; University of Stellenbosch. Faculty of Economic and Management Sciences. Dept. of Logistics.
ENGLISH ABSTRACT: The role of public transport is to stimulate urban, social, sustainable and economic developments by transport of passengers based on their needs with public transport organizations functioning as operators in this environment. This dissertation reports on the research done on resilience in urban public transport organizations; it presents the guiding principles and the framework of resilience and the ability of public transport organizations to embed this capability. The emerging discipline of resilience studies is multidimensional and multidisciplinary. The phenomenon has been examined to present a holistic perspective on resilience through an extensive review of the literature, supplemented by empirical research in the European public transport sector. Resilience has been defined as the capacity of an organization to survive, adapt and grow in the face of turbulent change. Existing research tends to focus on the relevance of the concept of resilience in a diversity of environments. There is little information or research that reflects the design principles and specific success factors in the public transport sector. The literature research produced several logical conclusions, which were reviewed by using structured interviews with a selected group of specialists in this field. This made it possible to determine guiding principles, to structure the framework, and to develop a unique classification of (i) the most fundamental vulnerability factors that make an organization susceptible to disruptions; and (ii) the capability factors as attributes required for sustained performance or accomplishment. All these findings are synthesised and this research establishes the ability of public transport organizations to implement a resilience approach within the boundaries of their level of advancement and prioritised direction statements. Recommendations for further research include extending the proposed framework empirically to other functions and to other organizations than urban public transport organizations.
Vragrangskikkings ter voorkoming van asmassalasgrens-oorskryding deur padkarweiers in Suid-Afrika
(Stellenbosch : Stellenbosch University, 2012-03) Jacobs, Cornelius Gregorius; Pienaar, W. J.; Stellenbosch University. Faculty of Economic and Management Sciences. Dept. of Logistics.
ENGLISH ABSTRACT: Road Tra c legislation prescribes constraints on the forces/loads which vehicles may exert on the road at contact surfaces or load points. These constraints have bearing on speci c contact surfaces or groups of contact surfaces. The constraints are in the form of maximum force values and maximum ratios, which may exist between forces. The forces exerted by a vehicle on the road is determined by a combination of the vehicle's own mass, dimensional characteristics, and the mass and position of its cargo. The mass and position of the cargo can be modelled by only considering its centroid. The centroid's position is linked to a certain cargo arrangement. It is necessary, in terms of legal constraints, to distinguish between legally permissable- and non-permissable arrangements. Methods are proposed in this dissertation to determine the borders for the position of the centroid according to cargo-mass, for a variety of vehicle con gurations. The determination of borders for the position of the centroid is the result of a three part process. Firstly, the legal limits are translated to mathematical inequalities that must be satis ed for the forces at contact surfaces. Secondly, conservative parametric estimates for the forces, in terms of the position and the mass of the centroid of a given vehicle, must be derived. Finally these estimates are incorporated into the load constraints and an enclosed permissable area for the centroid is found. These position constraints are suitable inputs to solution methods of various cargo arrangement problems. Linear programmes which can solve certain general arrangement problems by utilising the position constraints on the centroid, were successfully developed. Solutions are presented for the arrangement of pallet-freight, as well as the arrangement of cargo units with asymetrical centroids over the length or width of a vehicle's cargo area.

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