Dr. Iris Vis, Associate Professor

Iris F.A. Vis, Associate Professor of Logistics, Research Programme Chair of 'Distribution and Supply Chain Logistics'    


 

Research in logistics

Traffic jams of trains up to the Swiss border after an accident, frustrated customers at retailer Albert Heijn in a  response to numerous stock-outs during the so called 'Hamsterweken', millions of Euros tied up in inventories at hospitals, and waiting lines of over a mile of residents without their own cars eager to leave a city threatened by water.

These are just some examples where applying the right robust logistics planning and control techniques in the right way, at the right moment in the time might avoid or solve these kinds of daily problems. Developing these tools is one of the main research goals of the logistics group at the faculty of Economics and Business Administration at VU University Amsterdam.

Logistics in society
Basically, logistics operations can be noticed everywhere. More formally, logistics managers design, implement and control both forward and reverse flows of goods, services and related information in supply chains. Organisations must meet the tight deadlines and the ever increasing service requirements of their customers to remain competitive in a world that is changing continuously due to innovations in technology and communication. For example, retailers need to meet customer requirements, whereas disaster relief agencies attempt to help out affected people as quickly as possible. As a result, to keep our world in operation, both researchers in logistics and logistics managers are continuously searching for efficient and robust methods to regulate logistics processes, while improving costs, response times or customer service. For example, together with Sander de Leeuw and Delia Richardson, we are currently studying options to efficiently position aid goods all around the world such that response times to affected areas can be decreased dramatically in case disasters strike. Below some other research projects are described that all focus on designing new methods to assist in decision making in supply chains.

Behaviour of Customers
In classic inventory models in literature it is common to assume that excess demand is being backordered and delivered to the customer at a later point in time. However, we all know that when we experience a stock-out at, for example, a supermarket we either search for a substitute product or go elsewhere. In other words, customer behaviour in practice shows that unfulfilled demand can usually be considered as lost sales or that solutions should be provided by supply chains to keep the customer satisfied. For example, Albert Heijn experienced dramatic stock-outs during their last period of bargain sales. Local managers searched for ad-hoc solutions by offering substitute products with discount prices to avoid customers leaving the store empty handed. However, the main challenge is to design and develop a new class of inventory models that is capable of avoiding lost-sales and to deal with these challenges in general. Marco Bijvank developed a methodology to perform research in this area and designed new solution methods in his Ph.D. project 'Service Inventory Management'.

Dynamic solution approaches
As already demonstrated in the introduction, important characteristics of well performing supply chain techniques are that they allow for variations in both the outcomes and the moments at which the decision rules will be applied, to efficiently respond to changes in customer behaviour and limit expenses. These aspects are even more important during the current financial crisis. Currently, we focus together with Roel van Anholt and Lorike Hagdorn on developing dynamic inventory management approaches to ensure that banks can manage their inventories in ATMs in such a way that both investments and logistics costs can decrease while keeping customer service at a pre-defined level.

Internal logistics processes
Clearly, the overall supply chain is as strong as its weakest link! High levels of customer service can only be obtained if internal logistics processes in the supply chain are organised in the right way. Typical areas in the supply chain where such organisation is important include warehouses and container terminals, as well as rental organisations such as libraries in service oriented environments. Rental organisations face an additional challenge in meeting both customer and employee objectives in a single approach.  While customers need to be able to conveniently and comfortably find the products that meet their preference in attractively designed areas, employees face the challenge of organising front- and back-office processes, such as replacing individual returned items, as efficiently as possible. Together with Jaap Boter and Susanne Wruck we just started to develop models to address these logistics challenges in rental organisations by integrating techniques from both logistics and marketing.