Fraunhofer Chalmers Research Centre for Industrial Mathematics
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From Fish to Fish – Evaluating the Socio-Environmental Consequences of the Vietnamese Fishmeal Industry A Life Cycle Assessment and Product Chain Organisation Analysis of the Production of Vietnamese Fishmeal
No full textThe rapidly growing aquaculture industry in Vietnam has increased the demand for wild fish as a raw material for fishmeal and fishoil in processed feeds. While fishmeal and fishoil can be produced from fish by-products, in Vietnam it is generally produced from small pelagic fish or bycatch from local capture fisheries, otherwise known as ‘trashfish’. These fisheries have been associated with a range of negative environmental interactions, including disturbance of sea-floor ecosystems, poor energy efficiency, and reduction of juvenile fish. Moreover Edwards et al., (2004) review of Vietnamese fishmeal production reported that several of the fish stocks used were already overexploited and a recent report by the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) states that there will be no exploitable fish stocks in South East Asia by 2048 if current fishing practices continue.
As such, this study explored these environmental impacts using Life Cycle Assessment (LCA) and Product Chain Organisation (PCO) methodologies, with primary data collection in key parts of the fishmeal supply chain. This allowed for quantitative (LCA) and qualitative (PCO) representation of the status of the industry to be assessed, and for key Life Cycle Inventory data to be made publicly available.
The results from the LCA conducted show that the Vietnamese Large trawl fishing vessels (Anchovy trawlers) have the largest environmental impact for the Life Cycle Impact categories assessed in this study (Global Warming potential, Eutrophication, Acidification and Photochemical Oxidisation) relative to the functional unit of 1 tonne of Vietnamese fishmeal produced. The reason for this impact is a result of the quantity of trashfish this vessel class supplies to the fishmeal industry along with the fuel consumption per kg trashfish landed compared to the other vessel classes assessed. Along with this, when compared to other Vietnamese LCA studies that have used Peruvian or Danish fishmeal as a proxy, up to a 5x increase in environmental impact (based on impact categories assessed) can be seen in Vietnamese fishmeal.
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The results from the PCO indicate the important role middlemen play within the Vietnamese fishmeal industry with relation to, among others, the quality of trashfish that will be utilised for fishmeal production processes and the logistical support they provide. Moreover, it was seen that there are great sustainability improvements that could be made using the middlemen as a vector into the industry.
This thesis’s major flaw is that it lacks good biodiversity impact assessments that could be used as a baseline for comparison into the future. It is therefore suggested that the attention of further studies should be focused on environmental consequences of utilising trashfish for fishmeal and the subsequent biodiversity/ecosystem implications that these capture fisheries are associated with
Measurement, Judgment and Prediction of the Annoyance of the Noise Produced by Seat Belt Retractors
No full textThe automobile industry has grown sustainedly over the past decade. To enhance competitiveness, user experience and product details increasingly receive attention. Squeak and Rattle (S&R) are noises caused by the relative motion between installed components, in terms of friction and impact. The perceived annoyance of squeak and rattle noise from seat belt retractors, as might be expected, is nowhere near the sense of annoyance from other more significant sources, for instance, tires and engine. However, such a sort of objective noise is still audible and might be more predominant in future cars which have much better sound isolation.
In this thesis, three types of seat belt retractors are studied. They are both practically used inside Volvo cars. The primary objective is to design a sound quality metric for the squeak and rattle noise from seat belt retractors.
While recording the sounds, different recording environments, including laboratories and actual in-car environments, are seriatim tested. In order to obtain the perceived annoyance level of objective noises, a series of listening tests are performed in the form of MATLAB graphical user interface (GUI), with participants from different backgrounds involved. The listening test results are then combined with calculated psychoacoustic characters of sounds, thereby designing the corresponding sound quality metric using multiple linear regression
Connection of Electric Machine to a P2-X Transmission
No full textThis thesis aims at investigating two different mechanical connections by simulating
the performance regarding bearing force vibrations. The chosen mechanical connections
are a direct, helical, involute gear drive and a silent chain. The methodology
can be explained in four steps. First, mechanical transmission systems are studied
in order to choose the two mechanical connections to model and simulate. Second,
two models were built in the software MSC Adams. Third, the models were simulated
in the same software, and simulation results were produced. Finally, the
simulation results were analyzed, discussed and based on the analysis, the conclusion
that gear drive is more suitable based on the defined criterion’s’ compared to
chain drive. However, the results can be questioned by the fact that many assumptions
were made regarding the chain drive model. Additional, more granular models
and simulations of the chain drive are needed in order to be fully certain of the
conclusion
Understanding the Perceptions, Preferences, and Attitudes towards Investment through Digital Platform of a Big, Growing, and Young Customer Segment in Indonesia
No full textThe hype of digitalization has impacted several industries including finance. Several innovations have been launched such as robo-advisory investment platform which minimize the involvement of human in investment process. One of the companies that provides this service is company X which is based in Indonesia. On the other hand, there is a growing new segment which is projected to increase tremendously and is called ‘the billion dollars consumers’; muslim millennials. Company X aims to serve this growing segment thus understanding their needs and values become crucial aspect.
In this work, the researchers used quantitative methods and statistical analysis to study the behaviors of Indonesian Muslim millennials. The relation between financial literacy, Islamic financial literacy, and investment behavior is studied using factor analysis and t-test analysis. Online questionnaire was deployed to 379 respondents and analyzed further.
Findings suggest that in average both financial and Islamic financial literacies of the respondents are 58,5% and 54,3% respectively thus cannot be classified as sufficient. However, investors tend to have significantly higher financial literacy score than the non-investor group. In addition, the findings highlighted that investment decisions are driven mostly by religious beliefs and firm image, whereas digital solution is also seen as preferable and important. Consequently, the findings from this work will provide inputs for companies that are contemplating on targeting their goods at the fast-growing Indonesian Muslim millennials population