Fraunhofer Chalmers Research Centre for Industrial Mathematics
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Countermeasures for Impulsive Noise Character in Internal Combustion Engines
The demand for efficient vehicle propulsion has led to downsizing of the internal combustion engines. Combined
with a request for increased power output, these engines experience high peak pressures and strong pressure
gradients. The downsizing strategy has been found to induce noise that has an impulsive character. This
project investigates ways to counteract the transfer of this noise into the vehicle cabin. The assessment of the
impulsive noise character is based on the peak to average power ratio, spectrograms and subjective listening
of the vibration time history signal in the mounting points between the engine and the car. The evaluation
has also been aided by an overall sound pressure level estimate. The analysis is carried out using an existing
discretized model of a spark ignited four cylinder four stroke internal combustion engine. The influence of
material density, material stiffness, combustion strategy and bearing clearance on the generation of impulsive
noise character is investigated in a parameter study. Moreover, the possible mitigation of the noise character is
investigated in a design study, where the attachments in the engine structure of one of the mounting points
between the engine and the car are changed, while maintaining the position of the mounting point to the car.
It is concluded that an increased crank shaft stiffness, a prolonged combustion duration and a redesigned
suspension console are the three most efficient countermeasures to diminish the noise character
Agile project health indicators Project/Project portfolio Health indicators, frameworks and methods in agile projects.
Increased amount of complexity in the development of software projects have created the need for new non-traditional methods to run and organize projects. Agile is helping software companies to manage the complexity in their projects and teams to work more effectively towards effective project delivery. However, this methodology also brings uncertainties regarding the ways of working and there is a need for further clarifications and explorations in order to strive towards best practice. Finding accurate ways to ongoing measure the “health” of a project is one central aspect of this. Theory suggests that in order to work agile, one should decrease administrative work in order to help the project have an easy flow. However, the need to still measure end results on projects, is making companies adopt project management methods to work more agile. Having measurements will not only steer the projects towards plan, but it will also help to make more informed predictions of future outcomes. The aim of this master thesis is to suggest what kind of agile Key Performance Indicators are needed in order to measure the health of a project. A total of thirty-four interviews were conducted at different managerial levels in a software company in order to understand their ways of working with project management and agile. Data analysis identified current challenges and expectations for the future. Five different KPI are suggested and those are a combination of agile and non-agile project measurements. In this study, it was found out that the agile adoption in projects and project portfolio is very immature. There are still tension and uncertainties on how to work in agile, certain processes such as the measurements of projects need to be aligned to how agile works and the way it will work in the specific context. Measurements are good to predict the future, however if there is not a commitment from all the levels in the organization, these will not add any value to the projects. Hence commitment, transparency and collaboration among all the levels and in projects is key to have project success
Requirements on e-commerce distribution and their implications for the use of heavy trucks
The European market is experiencing a digital revolution and e-commerce shopping is a rapidly
increasing trend. E-commerce growth has accordingly led to increased logistical activities and
also driven a need for new flexible solutions of delivery. Stakeholders in the e-commerce
industry all have different requirement on the transportation and heavy truck manufacturers
today have their focus on fulfilling the needs of the stakeholders conducting the transport which
creates a gap in what is required and delivered. The aim of this thesis is to investigate how
heavy truck manufacturers can adapt to the e-commerce transport operations requirements in
the European market.
This qualitative study is based on secondary data and conducting interviews to triangulate the
issue and create a broad picture over relevant stakeholders and their requirements and
upcoming trends. Fifteen different interviews with eleven different organizations within the
realm of e-commerce, such as e-tailers, carriers, heavy truck manufacturer and external
stakeholders were conducted.
The thesis finds that the major trends in e-commerce are the growing cross-border market, the
demand for transparency and tracking throughout the distribution chain, the growing issues
with last mile and reverse logistics driven by retailers and customer behavior and requirements
on a higher service level of deliveries. New, more effective modes of delivery have started to
emerge with parcel lockers, click and collect and other more sustainable solutions. The thesis
discusses a misconception by e-tailers of customer requirements where the focus is mainly on
fast and convenient transport. Furthermore, it is discussed that transport is an important part of
e-commerce and that transport services should be priced and transparent.
The thesis concludes that e-commerce business is growing so fast that it is still under
development and the implications from customers behavior are hard to analyze. E-commerce
drives new modes of transport and delivery which puts requirement on the heavy truck
manufacturer to offer transport solutions with the possibility to communicate with and adapt to
other modes of transport and delivery