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Institute
Social media platforms play an increasing role in marketing, politics and police affairs, because they can strongly influence opinions. So called “opinion leaders” exert their influence in a given network and shape the opinions of other users. Identifying central nodes in a social graph has been of interest for decades. However, not all centrality measures were developed for social media platforms. They were built for social graphs, which did not include additional metrics (e.g. “likes”, “shares”). Nevertheless, these metrics play a crucial role on modern platforms. Hence, outdated measures need to be adjusted and additional metrics need to be integrated to ensure the best possible results.
In this work, the task is to cluster microarray gene expression data of the cyanobacterium Nostoc PCC 7120 for detection of messenger RNA (mRNA) degradation patterns. Searched are characteristic patterns of degradation which are caused by specific enzymes (ribonucleases) allowing a further biological investigation regarding biochemical mechanisms. The mRNA degradation is part of the regulation of gene expression because it regulates the amount and longevity of mRNA, which is available for translation into proteins. A particular class of RNA degrading enzymes are exoribonucleases which degrade the molecule from its ends, whereby a degradation from the 5’ end, the 3’ end or from both ends is theoretically possible.
In this investigation, the information about exoribonucleolytic degradation is given in a microarray data set containing gene expression values of 1,251 genes. The data set provides gene expression vectors containing the expression values of up to ten short distinct sections of a gene ordered from the genes 5’ end to its 3’ end. For each gene, expression vectors are available for both nitrogen fixing and non-nitrogen fixing conditions, which have to be considered separately due to biological reasons. Accordingly, after filtering and preprocessing, two datasets for clustering are obtained consisting of 133 ten-dimensional expression vectors. The similarity of the expression vectors is judged by a newly correlation based similarity measure and compared with the results obtained by use of the Euclidean distance. A non-linear transformation of the correlations was applied to obtain a dissimilarity measure. By choice of parameters within this transformation a user specific differentiation between negative and positive correlated gene expression vectors and an adequate adjustment regarding the noise level of gene expression values is possible.
Clustering was performed using Affinity Propagation (AP). The number of clusters obtained by AP depends on the so-called self-similarity for the data vectors. This dependence was used to identify stable cluster solutions by self-similarity control. To evaluate the clustering results, Median Fuzzy c-Means (M-FCM) was used. Further, several cluster validity measures are applied and visual inspections by t-distributed Stochastic Neighbor Embedding (t-SNE) as well as cluster visualization are provided for mathematical interpretation analysis of clusters.
To validate the clustering results biologically, the found data structure is checked for biological adequacy. A deeper investigation into the mechanisms behind mRNA-degradation was achieved by use of a RNA-Seq data set. Contained 40 (base pair) bp long reads for non-nitrogen fixing and nitrogen fixing conditions were assembled using bacteria-specific ab-initio assembly of Rockhopper. Thus, mRNA (transcript)-sequences of the clustered genes are obtained. A further investigation of the untranslated regions (UTRs) is performed here due to the assumption that exoribonucleases recognize specific transcript-sequences outside of the annotated gene regions as their binding sites. These UTRs need to be analyzed regarding sequence similarity using motif-finding algorithms.
In the context of globalization and the internationalization of international markets, mergers and acquisitions are becoming increasingly important for transnational corporations and national economies of countries as a form of internationalization, integration and the way to attract foreign investment. In the framework of this paper, the theoretical aspects of mergers and acquisitions have been analyzed, and the experience of Germany, China and Russia in attracting investments through mergers and acquisitions has been examined, and the success of this method for each country has been assessed.
DropConnect (the generalization of Dropout) is a very simple regularization technique that was introduced a few years ago and has become extremely popular because of its simplicity and effectiveness. In this thesis, a suitable architecture for applying DropConnect to Learning Vector Quantization networks is proposed along with a reference implementation and experimental results. Inmany classification tasks, the uncertainty of themodel is a vital piece of information for experts. Methods to extract the uncertainty and stability using DropConnect are also proposed and the corresponding experimental results are documented.
Abstract nicht vorhanden
The following is a description and outline of the work done at the Cornell Lab of Ornithology developing Nation Feathers VR, a virtual reality game for learning about bird calls and songs. The goal was to develop a game which is intuitive, educational and entertaining. Furthermore, the software needed to be structured in a way that allows for feasible future expansion. This required careful data saving and retrieval. The game gives the player an opportunity to learn and apply that knowledge, all while maintaining a shorter runtime in order to reduce the total time spent in the virtual world. This is meant to prevent any discomfort to the player that may result from extended use of the VR headset.
In this work, we discuss the key role that “conflict minerals” (Gold, Coltan, Cobalt, Tin, Tungsten) play in global supply chains and high-technology industries, and the issues surrounding their extraction and trade in origin
countries, particularly in the African Congo Basin and the Great Lakes Region. We discuss ongoing international efforts to combat violence, child labour and human rights violations at mineral extraction areas, particularly in the Democratic Republic of the Congo (DRC), where very large mineral reserves have been discovered. We present the OECD Due Diligence Guidance for Responsible Supply Chains of Minerals from Conflict-Affected and High-Risk Areas, and the
GOTS MineralTrace mineral proof-of-origin and trade chain certification solution developed by ibes AG in Germany, which automates and simplifies the implementation of the OECD Guidance. We discuss a pilot project in DRC involving the GOTS GoldTrace application, based on the MineralTrace platform. We point out MineralTrace’s benefits and its limitations. We analyse possible solutions to said limitations, including an analysis of blockchain-based transactional information exchange and record keeping systems, and finally we propose a new MineralTrace Application Programming Interface (API) that solves current limitations, introduces configuration flexibility for client applications, introduces workflow flexibility to adapt MineralTrace to any country or region, and simplifies data export functionality.
Object detection and classification is active field of research inmachine learning and computervision. Depending on the application there are different limitations to adjust to, but also possibilities to take advantage of. In my thesis, We focus on classification and detection of video sequence during night-time and the proposed method is robust since it does use image thresholding [8] which is commonly use in other methods and the thesis uses histograms of oriented gradients (HOG) [37] as features and support vector machine (SVM) [74] as classifier. It is of great importance that the extracted features from the images should be robust and distinct enough to help the classifier distinguish between high-beam and a low-beam. The classifier is part of the object detection which predicts whether or not a testing image matches one group or the other. In our case that is predicting whether or not an image belongs to high or low-beam sequence.
Success story DAB in the UK
(2017)
The popularity of digital audio broadcasting in different countries can be explained mainly by means of historical development. In this work, the general technical conditions are explained and the mode of operation is explained. In addition, advantages, disadvantages and alternatives are presented. After that, the development of the digital radio in Germany and the UK is compared with the current situation in order to show how the differences have led to a different distribution and acceptance of the medium.