The freight transport system is subject to delays and disturbances, which influence investment and planning decisions made by governments and infrastructure authorities. Traditionally relying on Cost Benefit Analysis (CBA) they are dependent on correct and up-to-date input data. So far, little success has been reached in estimating the effects of disturbances for freight. This paper aims to contribute to the understanding of disturbances in freight transport by reviewing and classifying the effects occurring due to transport time variability (TTV) and to suggest a calculation model to estimate the value of transport time variability (VTTV). In order to validate the model and its usability it was successfully tested in a case study for a large Swedish retail company. The effects of delays can be divided into four main types: System Killers, Catastrophic Events, Expected Risks, and Contingencies, of which the last two are relevant for VTTV. The model applies these in a two-step cost function with a fixed and variable part, building on previous studies of VTVV for passenger transport based on the scheduling utility approach. A main theoretical result is that the estimation of VTTV is derived mathematically independently of which measure that is chosen for the quantification of TTV.

The freight transport system is subject to delays and disturbances, which influence investment and planning decisions made by governments and infrastructure authorities. Traditionally relying on Cost Benefit Analysis (CBA) they are dependent on correct and up-to-date input data. So far, little success has been reached in estimating the effects of disturbances for freight.

This paper aims to contribute to the understanding of disturbances in freight transport by reviewing and classifying the effects occurring due to transport time variability (TTV) and to suggest a calculation model to estimate the value of transport time variability (VTTV). In order to validate the model and its usability it was successfully tested in a case study for a large Swedish retail company.

The effects of delays can be divided into four main types: System Killers, Catastrophic Events, Expected Risks, and Contingencies, of which the last two are relevant for VTTV. The model applies these in a two-step cost function with a fixed and variable part, building on previous studies of VTVV for passenger transport based on the scheduling utility approach. A main theoretical result is that the estimation of VTTV is derived mathematically independently of which measure that is chosen for the quantification of TTV.

Research in warehouse optimization has gotten increased attention in the last few years due to e-commerce. The warehouse contains a waste range of different products. Due to the nature of the individual order, it is challenging to plan the picking list to optimize the material flow in the process. There are also challenges in minimizing costs and increasing production capacity, and this complexity can be defined as a multidisciplinary optimization problem with an IDF nature. In recent years the use of parallel computing using GPGPUs has become increasingly popular due to the introduction of CUDA C and accompanying applications in, e.g., Python. 

In the case study at the company in the field of retail, a case study including a system design optimization (SDO) resulted in an increase in throughput with well over 20% just by clustering different categories and suggesting in which sequence the orders should be picked during a given time frame. 

The options provided by implementing a distributed high-performance computing network based on GPUs for subsystem optimization have shown to be fruitful in developing a functioning SDO for warehouse optimization. The toolchain can be used for designing new warehouses or evaluating and tuning existing ones. 

The basis for the thesis is to assess the usefulness of describing and analysing transportation and logistics systems as being complex systems. The reason and assumption being that in the future more integrated and sophisticated systems and solutions will be demanded. The requirements of the future will also be the requirements of a sustainable society and this also requires higher sophistication in that industry and consumers demand faster and cheaper solutions, but with less environmental impact. The ultimate goal is to use complexity to meet the demand for more sophisticated approaches, models and methods both to better understand these systems and to be able to manage and control them in the most efficient way. In this thesis the concept of complexity is applied to the context of transportation and logistics system in order to better understand the characteristics of these systems. It is an unorthodox method within the research area of transportation and logistics, but it is argued that the concept of complexity provides a valid and valuable model for the analysis of transportation and logistics systems. Complexity is throughout the thesis treated as an important aspect of transportation and logistics systems, and is as a concept used to describe, analyse and model transportation and logistics systems and their properties. The concept of complexity as well as other related concepts are analysed and a conceptual model of transportation and logistics systems' complexity is developed. This model describes the complexity of transportation and logistics systems as residing primarily within three core properties: the network, the process and the stakeholder properties. These properties in their turn are influenced by other extended properties such as variety, connectivity, cognition etc. Three different perspectives; the network, the process and the stakeholder perspectives are used to describe and analyse the transportation and logistics systems. The network perspective focuses primarily on the structure of the transportation and logistics systems, while the process perspective focuses on the activities and dynamics and the stakeholder perspective focuses on the perceptions, represented by the different stakeholders. Four empirical studies are used as a base for the analysis and these four studies are representative for four different aspects of transportation and logistics systems; terminals, supply chains, distribution channels and the transportation of passengers. A measure of transportation and logistics' systems complexity is also develop and applied to these different systems. These studies provide an empirical basis for the research problem studied as well as a validation of the usefulness of the conceptual model of complexity and the proposed measure.