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According to various studies, a strong market penetration of electric mobility is expected in the next few years. On the one hand, electric vehicles can contribute to achieve climate targets, but on the other hand, they can place a heavy burden on the power grid and have serious consequences, such as component overload and voltage instabilities, if they are charged in an uncoordinated manner.
Proper grid integration of electric vehicles with a coordinated charging approach can minimize these negative impacts and brings about positive aspects, such as improving grid quality and integrating larger amounts of renewable energy.
Taking into consideration the legal framework and the different requirements of network operators, vehicle manufacturers and owners, this paper compares different network integration techniques.
It is concluded that a decentralized charging management approach, in which the vehicle owners themselves make the charging decisions, is a good compromise between the different parties and consequently the best alternative for the grid integration of electric vehicles in Ger-many.
One aspect that needs further investigation is which is the best way to motivate vehicle owners to actively participate in a flexible charging management.
In this document a reliable data streaming mechanism for a TDMA LPWAN application is developed by adapting a link layer solution for power line communication, published at the International Symposium on Power Line Communications and its Applications (ISPLC) 2015. A C++ implementation of the services link layer is provided and demonstrated
working at a packet error rate of 50%.
This work aims to generate synthetic electromyographic (EMG) signals using Generative Adversarial Network (GAN). GANs are considered as one of the most exciting and promising approaches in deep learning [6], offering the possibility to generate artificial data based on real data. GAN consists of two main parts, a discriminator that attempts to differentiate between the generated data and the original data, and a generator that tries to fool the discriminator by generating data which looks like real data, the GAN works by staging a two-player
minimax game between generator and discriminator networks. To achieve the objective of generating realistic artificial electromyographic signals, two different architectures are considered for the generator and the discriminator networks of the GAN model: Long short-term memory (LSTM), which can avoid the long-term dependency problem and remembers information over a long period of time, and convolutional neural network (CNN), which is a powerful tool at automatic feature extraction. Different combinations of CNN and LSTM including hybrid model are experimented within the GAN using the same training data-set. The results and performances of each combination are compared and reviewed. The generated artificial EMG signals can be used to
simulate real muscle activity situations to for example improve muscle signal controlled prostheses using artificial data that may include conditions that does not exist in real data. This method of artificial data generation is not limited to EMG signals, the network can also be used to generate other synthetic biomedical signals such as electroencephalogram (EEG) or electrocardiogram (ECG) that can be practically used for testing algorithms and classifiers.
The goal of this empirical study is to answer whether predictions about stock price movements can be made with the use of machine learning in the energy sector and what influence contributions from social media have on its development. To answer the research
question, the social media platforms Twitter and Reddit, in terms of the suitability of the information, were studied and evaluated. Then, the sentiments of the posts from social media were collected and used in machine learning models. The models include the Gradient Boosted Regression Tree, Multilayer Perceptron, and Long Short-Term
i Memory, which predict a subsequent day's closing stock price. The study showed that deviations from predictions of stock price movements of 1.05 % are possible and further sentiment values do not show significant positive effect on reducing the error value. The
result shows that the collected sentiments from the social media platform Twitter have no positive effect on the stock price movements within the energy industry.
Keywords: stock market, stock prediction, artificial neural networks, machine learning,
energy market, sentiment analysis
Prediction of movement onset and direction based on muscle activity during reaching movements
(2021)
Electromyography as a technology allows one to be able to measure muscle activity, which in turn can be used to detect movement direction and onset. The process for this classification problem often involves a multitude of various extracted features and classification techniques, that differ a lot across different scientific papers. This thesis analyzed different features and classifiers and tackled a center out reaching task to determine a good workflow for classifying
arm movement direction. The data was recorded with 6 sEMG electrodes
placed on the upper arm of 5 healthy participants.
The different experiments show good classification accuracy of over 96 % in a reaching task with 16 targets placed in a circle within reaching distance. The results also show that the classification accuracy did not differ a lot between features. The individual EMG channels also display high correlation, which suggests a possible reduction in necessary electrodes. Classification accuracy
before movement onset also only dropped by 2 % compared to the accuracy of the whole time window of a reaching motion. This seems especially vital to ensure proper support via prosthesis or orthesis for people with heavily impaired movement.
This study aims to determine the competing concerns of people interested in startup development and entrepreneurship by using topic modeling and sentiment analysis on a social question-and-answer (SQA) website. Understanding the underlying concerns of startup entrepreneurs is critical to society and economic growth. Therefore, greater scientific support for entrepreneurship remains necessary, including data mining from virtual social communities. In this study, an SQA platform was used to identify the sentiment of thirty concerns of people interested in startup entrepreneurship. Based on topic modeling and sentiment analysis of 18819 inquiries in various forums on an SQA, we identified additional questions about founder figures, keys to success, and the location of a startup. In addition, we found that general questions were rated more positively, especially when it came to pitching, finding good sources, disruptive innovation, idea generation, and marketing advice. On average, the identified concerns were considered 48.9 percent positive, 41 percent neutral, and 10.1 percent negative. This research establishes a critical foundation for future research and development of digital startups by outlining a variety of different concerns associated with startup development in the digital age.
This study proposes a framework for the collaborative development of global start-up innovators in a multigenerational digital environment. Intergenerational collaboration has been identified as a strategy to support entrepreneurs during their formative years. However, integrating and fostering intergenerational collaboration remains elusive. Therefore, this study aims to identify competencies for successful global start- ups through intergenerational knowledge transfer. We used a systematic literature review to identify a competency set consisting of growth virtues, effectual creativity, technical domain, responsive teamwork, values-based organization, sustainable networking, cultural awareness, and facilitating intergenerational safety. The competency framework serves as a foundation for knowledge management research on the global innovation readiness of people to collaborate across generations in the digital age.
So far, researchers have used a wellbeing-centered approach to catalyze successful intergenerational collaboration (IGC) in innovative activities. However, due to the subject’s multidisciplinary nature, there is still a dearth of comprehensive research devoted to constructing the IGC system. Thus, the purpose of this study is to fill a research void by providing a conceptual framework for information technology (IT) system designers to use as a jumping-off point for designing an IGC system with a wellbeing-oriented design. A systematic literature study was conducted to identify relevant terms and develop a conceptual framework based on a review of 75 selected scientific papers. The result consists of prominent thematic linkages and a conceptual framework related to design technology for IGC systems. The conceptual framework provides a comprehensive overview of IGC systems in the innovation process by identifying five barrier dimensions and using six wellbeing determinants as IGC catalysts. Moreover, this study discusses future directions for research on IGC systems. This study offers a novel contribution by shifting the technology design process from an age-based design approach to wellbeing-driven IGC systems. Additional avenues for investigation were revealed through the analysis of the study’s findings.
Proceedings of DELFI Workshops 2021
13.09.2021
Dortmund (Online), Deutschland