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The Internet of Things (IoT) is a fast-growing, technological concept, which aims to integrate various physical and virtual objects into a global network to enable interaction and communication between those objects (Atzori, Iera and Morabito, 2010). The application possibilities are manifold and may transform society and economy similarly to the usage of the internet (Chase, 2013). Furthermore, the Internet of Things occupies a central role for the realisation of visionary future concepts, for example, Smart City or Smart Healthcare. In addition, the utilisation of this technology promises opportunities for the enhancement of various sustainability aspects, and thus for the transformation to a smarter, more efficient and more conscious dealing with natural resources (Maksimovic, 2017). The action principle of sustainability increasingly gains attention in the societal and academical discourse. This is reasoned by the partly harmful consumption and production patterns of the last century (Mcwilliams et al., 2016). Relating to sustainability, the advancing application of IoT technology also poses risks. Following the precautionary principle, these risks should be considered early (Harremoës et al., 2001). Risks of IoT for sustainability include the massive amounts of energy and raw materials which are required for the manufacturing and operation of IoT objects and furthermore, the disposal of those objects (Birkel et al., 2019). The exact relations in the context of IoT and sustainability are insufficiently explored to this point and do not constitute a central element within the discussion of this technology (Behrendt, 2019). Therefore, this thesis aims to develop a comprehensive overview of the relations between IoT and sustainability.
To achieve this aim, this thesis utilises the methodology of Grounded Theory in combination with a comprehensive literature review. The analysed literature primarily consists of research contributions in the field of Information Technology (IT). Based on this literature, aspects, solution approaches, effects and challenges in the context of IoT and sustainability were elaborated. The analysis revealed two central perspectives in this context. IoT for Sustainability (IoT4Sus) describes the utilisation and usage of IoT-generated information to enhance sustainability aspects. In contrast, Sustainability for IoT (Sus4IoT) fo-cuses on sustainability aspects of the applied technology and highlights methods to reduce negative impacts, which are associated with the manufacturing and operation of IoT. Elaborated aspects and relations were illustrated in the comprehensive CCIS Framework. This framework represents a tool for the capturing of relevant aspects and relations in this context and thus supports the awareness of the link between IoT and sustainability. Furthermore, the framework suggests an action principle to optimise the performance of IoT systems regarding sustainability.
The central contribution of this thesis is represented by the providence of the CCIS Framework and the contained information regarding the aspects and relations of IoT and sustainability.
The goal of this thesis is to create a recommender system (RS) for business processes, based on the existing ProM plugin RegPFA. To accomplish this task, firstly an interface must be created that sets up and expands a database receiving probabilistic finite automata (PFA) created by RegPFA in tsml format as input. Secondly, a Java program must be designed that uses said database to recommend the process elements that are most likely to follow a given sequence of process elements.
Business Process Querying (BPQ) is a discipline in the field of Business Process Man- agement which helps experts to understand existing process models and accelerates the development of new ones. Its queries can fetch and merge these models, answer questions regarding the underlying process, and conduct compliance checking in return. Many languages have been deployed in this discipline but two language types are dominant: Logic-based languages use temporal logic to verify models as finite state machines whereas graph-based languages use pattern matching to retrieve subgraphs of model graphs directly. This thesis aims to map the features of both language types to features of the other to identify strengths and weaknesses. Exemplarily, the features of Computational Tree Logic (CTL) and The Diagramed Modeling Language (DMQL) are mapped to one another. CTL explores the valid state space and thus is better for behavioral querying. Lacking certain structural features and counting mechanisms it is not appropriate to query structural properties. In contrast, DMQL issues structural queries and its patterns can reconstruct any CTL formula. However, they do not always achieve exactly the same semantic: Patterns treat conditional flow as sequential flow by ignoring its conditions. As a result, retrieved mappings are invalid process execution sequences, i.e. false positives, in certain scenarios. DMQL can be used for behavioral querying if these are absent or acceptable. In conclusion, both language types have strengths and are specialized for different BPQ use cases but in certain scenarios graph-based languages can be applied to both. Integrating the evaluation of conditions would remove the need for logic-based languages in BPQ completely.
Our work finds the fine grained edits in context of neighbouring tokens in Wikipedia articles. We cluster those edits according to similar neighbouring context. We encode neighbouring context into vector space using word vectors. We evaluate clusters returned by our algorithm on extrinsic and intrinsic metric and compare it with previous work. We analyse the relation between extrinsic and intrinsic measurements of fine grained edit tokens.
In this thesis, I present the results of my studies on taxonomy, systematics, and biogeography of Impatiens (Balsaminaceae) in Madagascar and the Comoro islands.
In Chapter 1 I reviewed the literature on taxonomy and classification of Balsaminaceae, on habitat, world distribution, morphology, molecular phylogenetics and infrageneric classification of the genus Impatiens. In Chapters 2-15 (Fischer & Rahelivololona 2002, 2003, 2004, 2007, 2015a, 2015b, 2015c, 2016, Fischer et al. 2004. 2017, 2018a, b submitted, Rahelivololona et al. 2003) I presented the first results of a revision of Balsaminaceae of Madagascar and the Comoro islands including the description of 78 new species. In Chapter 16 (Yuan et al. 2004) we worked on the phylogeny and biogeography of Balsaminaceae inferred from ITS sequences using combined results from molecular phylogenetic and morphological analyses. In Chapter 17 (Rahelivololona et al. 2018) we conducted a phylogeny and assessment of the infrageneric classification of species in the Malagasy Impatiens (Balsaminaceae) with a particular emphasis on taxa collected from Marojejy.
Below I summarise the most important findings of each chapter and provide an outlook for future studies.
How many species of Impatiens occur in Madagascar and the Comoro islands?
To provide additional information on the taxonomic revision of Impatiens in Madagascar and the Comoro islands, the identification of already described species as well as the description of new species was conducted. Based on herbarium specimens from BR, G, K, NEU, P, TAN and on living plants collected during several field trips, 78 new species and 6 nomina nova have been published and another 70 new taxa are already identified. Actually more than 260 species occur in Madagascar and the Comoro islands and all of them are endemic. For each species, a description of the morphology, phenology, ecology and known distribution range was provided. Apart from new taxa, the delimitation of already described species like Impatiens firmula Baker and Impatiens hildebrandtii Baill. could be clarified by studying the types and by observing the variability in the field.
Are the groups of Impatiens in Madagascar monophyletic, and what is the systematic position of Trimorphopetalum?
Yuan & al. (2004) conducted a molecular phylogenetic study to examine the morphological and karyological evolution, and the historical biogeography of the Balsaminaceae family by using nucleotide sequence data of internal transcribed spacer regions of nuclear ribosomal DNA. The results support the monophyly of the Malagasy endemic section Trimorphopetalum and show that the cleistogamous Impatiens inaperta should be included in the sect. Trimorphopetalum which is the most derived within Impatiens. Therefore, the section Preimpatiens proposed by Perrier de la Bâthie (1934) is paraphyletic.
Rahelivololona & al. (2018) provided a phylogenetic study focused on three subdivisions (based on macromorphological characters) proposed by Perrier de la Bâthie (1934). The analysis was done using two nuclear AP3/DEF homologues (ImpDEF1 and ImpDEF2) and the plastid atpB-rbcL spacer to reassess or assess the monophyly of the Malagasy Impatiens, of the sections Preimpatiens (Humblotianae and Vulgare groups) and Trimorphopetalum. A focus was on the species of Impatiens from the Marojejy National Park and of the morphologically variable species I. elatostemmoides, I. “hammarbyoides”, I. inaperta and I. manaharensis, using monophyly as the primary criterion.
As results the Malagasy Impatiens are paraphyletic and the section Preimpatiens sensu Perrier de la Bâthie (1934) (= subgen. Impatiens sensu Fischer & Rahelivololona 2002) was not resolved as a monophyletic group. The section Trimorphopetalum sensu Perrier de la Bâthie (1934) (= subgen. Trimorphopetalum sensu Fischer & Rahelivololona 2002), however, was strongly confirmed as a monophyletic lineage (BS: 92; BPP: 1). Neither the Humblotianae group nor the Vulgare group was supported as monophyletic. None of the morphologically variable species appeared to be monophyletic and the sampled species of Impatiens from the Marojejy National Park do also not form a monophyletic group.
What are the biogeographical position and the distribution patterns of Impatiens in Madagascar and the Comoro islands?
Investigation of the geographical affinities and species distribution of section Impatiens (including Humblotianae group and Vulgare group) and section Trimorphopetalum were conducted and the origin and evolution as well as species richness and endemism were discussed.
The isolation, the climate and the complex topography of Madagascar have generated the microhabitats and ecological niches favourable to the diversification of Impatiens species. Impatiens of Madagascar with 260 endemic species is actually the largest genus in Madagascar. Therefore, Madagascar and the Comoro islands are among the most species-rich regions in the world for Impatiens.
Future studies
In Impatiens on Madagascar, there remain numerous unresolved questions that need to be adressed:
• A further study based on a much larger molecular data set and sampling from the entire geographic ranges of Impatiens in Madagascar is needed to retest the monophyly of the different subgenera and sections, as well as a molecular dating of the Malagasy Impatiens.
• The study of pollinators as a key for understanding the radiation and species richness is required: Within Impatiens the different shapes of spur are related to pollinators (bees, birds, butterflies and moths). Therefore pollinator observation of specific species need to be done to understand the radiation of species by adaptation and coevolution with these pollinators. A pollination study with a large number of species within section Trimorphopetalum will help to understand the mechanism of complete disappearance of the spur, the shift of pollinators and the evolution of species richness.
• The destruction of the natural habitats of Impatiens and the subsequent reduction of humidity in logged area constitute a severe threat for the survival of many species. The conservation and reforestation of vulnerable areas such as Ankaratra, Daraina, Mandraka and Col des Tapia near Antsirabe is required.
• In terms of conservation and to mitigate the threat on the genus, a study on the ex-situ-conservation of Malagasy Impatiens species is very important as long as some species are suitable for horticultural purposes (e.g. Impatiens mayae-valeriae, Impatiens emiliae and species with broad red spur).
• Finally, the publication of the revision of Impatiens of Madagascar and the Comoro islands will help other botanists to identify the species and will thus increase our knowledge on the group.
Tracking is an integral part of many modern applications, especially in areas like autonomous systems and Augmented Reality. For performing tracking there are a wide array of approaches. One that has become a subject of research just recently is the utilization of Neural Networks. In the scope of this master thesis an application will be developed which uses such a Neural Network for the tracking process. This also requires the creation of training data as well as the creation and training of a Neural Network. Subsequently the usage of Neural Networks for tracking will be analyzed and evaluated. This includes several aspects. The quality of the tracking for different degrees of freedom will be checked as well as the the impact of the Neural Network on the applications performance. Additionally the amount of required training data is investigated, the influence of the network architecture and the importance of providing depth data as part of the networks input. This should provide an insight into how relevant this approach could be for its adoption in future products.
Grapevine growers have struggled with defending their crops against pests and diseases since the domestication of grapevine over 6000 ears ago. Since then, new growing methods paired with a better nderstanding of the ecological processes in the vineyard ecosystem continue to improve quality and quantity of grape harvests. In this thesis I am describing the effects of two recent innovations in viticulture on pest and beneficial arthropods in vineyards; Fungus-resistant grapevine cultivars (PIWIs) and the pruning system semi-minimal pruned hedge (SMPH). The SMPH pruning system allows for a drastic reduction of manual labor in the vineyard, and PIWIs are resistant to two of the most common fungal diseases of grapevine and therefore allow a drastic reduction of fungicide applications compared to conventional varieties. Heavy use of pesticides is linked to a number of problems, including pollution of waterways, negative effects on human health, and biodiversity loss. Here, I studied the effects of fungicide reduction and minimal pruning on arthropods that are beneficial for natural pest suppression in the vineyard ecosystem such as predatory mites, spiders, ants, earwigs, and lacewings. All of these groups either benefitted from the reduction of fungicide sprayings or were not significantly affected. Structural changes in the canopy of SMPH grapevines altered the microclimate in the canopy which in turn influenced some of the arthropods living in it. Overall, my findings suggest that PIWIs and SMPH, both in combination or separately, improve conditions for natural pest control. This adds to other advantages of these innovative management practices such as a reduction in production cost and a smaller impact on the environment.
Willingness to pay and willingness to accept on a two-sided platform - The use case of DoBeeDo
(2019)
It is widely known that especially for technology-based start-ups, entrepreneurs need to set up the boundaries of the business and define the product/service to offer in order to minimize the risk of failure. The goal of this thesis is to not only emphasize the importance of the business model development and evaluation but also show an example customer validation process for an emerging start-up named DoBeeDo, which is a mobile app operating on a two-sided market. During the process of customer validation a survey has been conducted to evaluate the interest of the target groups as well as the fit of their expectations using the Willingness to Pay and Willingness to Accept measures. The paper includes an analysis and evaluation of the gathered results and assesses whether the execution of the Customer Development Model can be continued.
Commonsense reasoning can be seen as a process of identifying dependencies amongst events and actions. Understanding the circumstances surrounding these events requires background knowledge with sufficient breadth to cover a wide variety of domains. In the recent decades, there has been a lot of work in extracting commonsense knowledge, a number of these projects provide their collected data as semantic networks such as ConceptNet and CausalNet. In this thesis, we attempt to undertake the Choice Of Plausible Alternatives (COPA) challenge, a problem set with 1000 questions written in multiple-choice format with a premise and two alternative choices for each question. Our approach differs from previous work by using shortest paths between concepts in a causal graph with the edge weight as causality metric. We use CausalNet as primary network and implement a few design choices to explore the strengths and drawbacks of this approach, and propose an extension using ConceptNet by leveraging its commonsense knowledge base.
Thesis is devoted to the topic of challenges and solutions for human resources management (HRM) in international organizations. The aim is to investigate methodological approaches to assessment of HRM challenges and solutions, and to apply them on practice, to develop ways of improvement of HRM of a particular enterprise. The practical research question investigated is “Is the Ongoing Professional Development – Strategic HRM (OPD-SHRM) model a better solution for HRM system of PrJSC “Philip Morris Ukraine”?”
To achieve the aim of this work and to answer the research question, we have studied theoretical approaches to explaining and assessing HRM in section 1, analyzed HRM system of an international enterprise in section 2, and then synthesized theory and practice to find intersection points in section 3.
Research findings indicate that the main challenge of HRM is to balance between individual and organizational interests. Implementation of OPD-SHRM is one of the solutions. Switching focus from satisfaction towards success will bring both tangible and intangible benefits for individuals and organization. In case of PrJSC “Philip Morris Ukraine”, the maximum forecasted increase is 330% in net profit, 350% in labor productivity, and 26% in Employee Development and Engagement Index.