Parental care in relation to offspring sex and mate attractiveness in the Blue Tit

The aim of this thesis is to determine whether differential allocation, sex biased care or differential sex-biased care occurs in blue tits. By videotaping feeding rates of blue tits and by determining the sex of offspring using molecular techniques, we can measure the amount of parental care by male and female blue tits in each sex of offspring. By measuring the UV-colouration of the parents, we are able to determine how much is invested in the total brood and in each offspring sex in relation to parental attractiveness.

Elasticity Measurement in CaaS Environments - Extending the Existing BUNGEE Elasticity Benchmark to AWS\u27s Elastic Container Service

Rapid elasticity and automatic scaling are core concepts of most current cloud computing systems. Elasticity describes how well and how fast cloud systems adapt to increases and decreases in workload. In parallel, software architectures are moving towards employing containerised microservices running on systems managed by container orchestration platforms. Cloud users who employ such container-based systems may want to compare the elasticity of different systems or system settings to ensure rapid elasticity and maintain service level objectives while avoiding over-provisioning. Previous research has established a variety of metrics to measure elasticity. Some existing benchmark tools are designed to measure elasticity in “Infrastructure as a Service” (IaaS) systems, but no research exists to date for measuring elasticity in systems based on containers and container orchestration. In this dissertation, an existing benchmark designed for IaaS systems, the BUNGEE benchmark developed at the University of Würzburg, was extended to be applicable to Amazon’s Elastic Container Service, a container-based cloud system. An experiment was conducted to test if the extension of the BUNGEE benchmark described in this dissertation delivers reproducible results and is therefore valid. For validation, the crucial phase of the benchmark - the system analysis phase - was run 32 times. It was established with statistical tests if the results vary by more than the acceptable level. Results indicate that there is some amount of variability, but it does not exceed the acceptable level and is consistent with the amount of performance variability encountered by other researchers in Amazon’s cloud systems. Therefore, it is concluded that the BUNGEE benchmark is likely applicable to container-based cloud systems. However, some parameters and configuration settings specific to container orchestration systems were identified that could impede reproducibility of results and should be considered in future experiments

Empty Container Management in the Benelux Waterways

The scientific contribution of this paper is the development of a model for empty container management in the hinterlands of the ports of Antwerp and Rotterdam. The objective of the proposed model is to minimize the total operational cost while satisfying the demand for empty containers. This goal is achieved by choosing the most efficient transportation mode between a seaport and its hinterland: road, inland waterways or intermodal transport. Moreover, to fit the real-life operation and management as well as possible, our model also includes container substitution and container leasing options.Peer reviewe

Rail-Road terminal locations: aggregation errors and best potential locations on large networks

In network location problems, the number of potential locations is often too large in order to find a solution in a reasonable computing time. That is why aggregation techniques are often used to reduce the number of nodes. This reduction of the size of the location problems makes them more computationally tractable, but aggregation introduces errors into the solutions. Some of these errors will be estimated in this paper. A method that helps to isolate the best potential locations for rail-road terminals embedded in a hub-and-spoke network will further be outlined. Hub location problems arise when it is desirable to consolidate flows at certain locations called hubs. The basic idea is to use the flows of commodities and their geographic spreading as input to determine a set of potential locations for hub terminals. The exercise will be done for the trans-European networks. These potential locations can then further be used as input by an optimal location method

Three dimensional Bin Packing Problem applied to air transport

Packing boxes into containers is a daily process in many di erent elds and especially in transport. However, the particular case of air transport brings some new constraints such as the stability or the fragility of the cargo. The distribution of the weight has also to be considered. Moreover, this special case also brings some data such as the dimensions of the possible containers, called Unit Load Devices. This paper is concerned with the formulation of the three dimensional palletization which includes the main constraints met in the air cargo industry. It proposes a integer linear program for this combinatorial optimization problem

Road and intermodal transport performance: the impact of operational costs and air pollution external costs

peer reviewedThe transportation of goods is essential for the economy, but it also contributes to air pollution which, in turn, affects human health. These negative impacts generate additional costs for society that are not necessarily taken into account in public transportation policies and in private transportation decisions of companies and individuals. This leads to inefficient transportation systems where the social equilibrium is not reached. Intermodal transport is promoted by the European Commission to reduce these negative externalities. The objective of this paper is to analyze at a strategic level the effect on modal split between road, intermodal rail and intermodal inland waterway transport of several economic or environmental policies. An intermodal allocation model is applied to the Belgian case in order to identify the modal split changes between the single minimization of costs (operational or health-related external) and the introduction of additional road taxes

The sensitivity of optimal rail‐road terminal locations to intermodal freight costs variations

In the last decades, the market of goods became globalized, increasing international trade relations and the demand for long distance transportation. As a consequence of the larger distances traveled and of the containerization of goods, maritime transportation became more efficient and reliable. In the hinterland, intermodal (rail-road) freight transportation emerged as a competitive alternative to truck-only transportation. In one of its possible meanings, intermodal freight transportation is the multimodal chain of container-transportation services [1] that, e.g., brings containers from (or to) the seaport by barge or rail to (or from) an intermodal terminal in the hinterland from where they are shipped by truck to their final destination (or origin). This study focus on inland intermodal freight transport, in particular, on the rail–truck transport of cargo containers in Belgium. This European country has a long rail system and in the last years has readapted this system in order to handle with containerized cargo. Since 2004, some rail-road terminals have been built and new intermodal services between the seaports of Belgium have been established. In addition, with the aim of promoting the modal share of intermodal rail-road transport, the federal government of Belgium started subsidizing part of the rail transport cost and of the transshipments costs at the rail-road terminals. With these investments the intermodal freight flows in Belgium have increased

Inland intermodal freight transport modelling

peer reviewedThe demand for goods has grown in the past decades, in such a way that today freight transport has become essential for the support of modern economies. The search for a competitive freight transport system, able to cope with the growing freight flows, has lead in the last decades to large investments in intermodal transport options, mainly in Europe and North America. Intermodal freight transport is the movement of goods done with the same loading unit (or vehicle) by successive modes of transport, without handling the goods themselves when changing the modes. This paper focus on inland intermodal freight transport, in particular, on the rail?truck transport of cargo containers in Belgium. The work aims to discuss the strategic decision of locating the rail-truck intermodal terminals in Belgium, in which freight can change between modes, while tacking into account the containerized cargo flows between the seaports of Belgium (Antwerp, Zeebruge, Ghent, and Ostend), the main generation centres in Belgium, and the generation centres at the border regions of neighbouring countries. The competitiveness of rail-truck networks in comparison of truck-only is discussed, in particular, for a relative small country as Belgium