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In the past few years Generative models have become an interesting topic in the field of Machine Learning (ML). Variational Autoencoder (VAE) is one of the popular frameworks of generative models based on the work of D.P Kingma and M. Welling [6] [7]. As an alternative to VAE the authors in [12] proposed and implemented Information Theoretic Learning (ITL) based Autoencoder. VAE and ITL Autoencoder are a combination of the neural networks and probabilistic graphical models (PGM) [7]. In modern statistics it is difficult to compute the approximation ofthe probability densities. In this paper we make use of Variational Inference (VI) technique from machine learning that approximate the distributions through optimization. The closeness between the distributions are measured by the information theoretic divergence measures such as Kullbach-Liebler, Euclidean and Cauchy Schwarz divergences. In this thesis, we study theoretical and experimental results of two different frameworks of generative models which generate images of MNIST handwritten characters [8] and Yale face database B [3]. The results obtained show that the proposed VAE and ITL Autoencoder are capable of generating the underlying structure of the example datasets
Digital data is rising day by day and so is the need for intelligent, automated data processing in daily life. In addition to this, in machine learning, a secure and accurate way to classify data is important. This holds utmost importance in certain fields, e.g. in medical data analysis. Moreover, in order to avoid severe consequences, the accuracy and reliability of the classification are equally important. So if the classification is not reliable, instead of accepting the wrongly classified data point, it is better to reject such a data point. This can be done with the help of some strategies by using them on top of a trained model or including them directly in the objective function of the desired training model. We discuss such strategies and analyze the results on data sets in this thesis.
This Bachelor thesis investigates the learning rules of the Hebbian, Oja and BCM neuron models for their convergence to, and the stability of, the fixed points. Existing research is presented in a structured manner using consistent notation. Hebbian learning is neither convergent nor stable. Oja learning converges to a stable fixed point, which is the eigenvector corresponding to the largest eigenvalue of the covariance matrix of the input data. BCM learning converges to a fixed point which is stable, when assuming a discrete distribution of orthogonal inputs that occur with equal probability. Hebbian learning can therefore not be used in further applications, where convergence to a stable fixed point is required. Furthermore, this Bachelor thesis came to the conclusion that determining the fixed points of the BCM learning rule explicitly involves extensive calculation and other methods for verifying the stability of possible fixed points should be considered.
This scientific work deals with the current opportunities of business development. Purpose of the work is study and analysis of the organization's development strategy and its development. The subject of the study is the mechanism of formation of an organization's development strategy, understanding of business development and its core methodologies and branches. This thesis is based on the operations of the real engineering company and main part of the research could be applied in reality. Main goal of the thesis is to find recommendations on the implementation of strategic changes organization's development strategy.
Simulating complex physical systems involves solving nonlinear partial differential equations (PDEs), which can be very expensive. Generative Adversarial Networks (GAN) has recently been used to generate solutions to PDEs-governed complex systems without having to numerically solve them.
However, concerns are raised that the standard GAN system cannot capture some important physical and statistical properties of a complex PDE-governed system, along side with other concerns for difficult and unstable training, the noisy appearance of generated samples and lack of robust assessment methods of the sample quality apart from visual examination. In this thesis, a standard GAN system is trained on a data set of Heat transfer images. We show that the generated data set can capture the true distribution of training data with respect to both visual and statistical properties, specifically the vertical statistical profile. Furthermore, we construct a GAN model which can be conditioned using variance-induced class label. We show that the variance threshold t = 0. 01 constructs a good conditional class label, such that the generated images achieve 96% accuracy
rate in complying with the given conditions.
Current research in identity management is focusing on decentralized trust establishment for distributed identities. One of these decentralized trust models is Self-Sovereign Identities (SSI). With SSI each entity should be able to independently present and manage provable information about itself as well as request and review evidence from other entities. Using a distributed blockchain, information for verifying the authenticity of this evidence can be obtained from any other entity. This concept can be used not only for people, but also for authentication and authorization during the life cycle of devices in the Internet of Things (IoT). This paper presents an SSI-based concept for authentication and authorization of IoT devices among each other, intended to contribute to the change in trust on the internet. The SSI methodology employing a blockchain offers the possibility to establish mutual trust and proof of ownership without relying on any third party. The paper describes the concept, offers a reference implementation, and gives a discussion of the approach.
As economies are getting more and more interconnected, the importance of the global logistics sector grew accordingly. However, both structural challenges and current events lead to recent supply chain disruptions, exposing the vulnerabilities of the sector. Simultaneously, blockchain has emerged as a key innovative technology with use cases going far beyond the exchange of virtual currencies. This paper aims to analyze how the technology is transforming global logistics and its challenges. Therefore, six use cases, are presented to give an overview of the technological possibilities of blockchain and smart contracts. The analysis combines theoretical approaches from scientific journals and combines them with findings from real-world implementations. The paper finds that the technology can change supply chain design fundamentally, with processes and decisions being automated and power within supply chain structures changing. However, implementations also face technological, environmental, and organizational challenges that need to be solved for wide-spread adoption.
More than 10 years after the invention of Bitcoin, the underlying blockchain technology is having an increasing effect on today’s society. Although one of the most popular application areas of blockchain is still the field of cryptocurrencies, the technological concepts are crossing into further application domains such as international supply chains. Fast-changing markets, high costs of time and risk management as well as biased relationships between the actors pose big challenges to an appropriate supply chain management. Based on a case study about sensor tracking, this paper explores the potential impact of blockchain on small and medium enterprises within an international supply chain. We will show that blockchain technologies offers a high potential to reduce inequalities of power relations between involved actors within supply chains. To achieve this, the requirements for the use of blockchain in supply chain management will be analyzed by means of a conducted case study and an expert survey of the companies concerned.
Digital Power of Attorney catalyzed by Software Requirements for Blockchain-based Applications
(2022)
Blockchain Technology (BT) with so-called web3 is at an inflection point between new sub-theme hypes and world-wide industrialization over last three years thanks to large companies like MicroStrategy [1], Facebook [2] and several Venture-Capital formations [3] who are already fighting over market share and community growth. Our work represents insights from Literature-based Software Requirement (SR) elicitation for a specific Blockchain-based Application, which is creation, managing and control of digital Power of Attorney (POA). The context of POA is not only a financial driven use-case it is by far a heavy weight universal legal transaction. We use a morphological box and reduced PRIMS-P to synthesis a generic specification for further Blockchain-based Application development. Formulated SRs in POA context are reflected on our core actors which are Grantor and authorized, trusted, external Entities. Proposed characteristics for relationship and effects are visualized in a reference model originally used in digital platform ecosystems [4]. This design and modelling approach facilitated closing discussion of BT and its future eCommerce perspective.
Dynamic object roles and corresponding contexts can model complex applications with higher-level abstraction. These abstracted applications can be used in wider areas such as financial institutions, health care, and supply chain network. Role management which consists of the creation of role objects, and binding role object between core objects still suffers from non-intrusive logging-monitoring, auditing, and resilient data source for role-based applications. Moreover, immutable smart contracts cause problems concerning bug fixing and maintenance without dynamic binding to new smart contract objects. An object that is created from a smart contract (contract class) can be transparently attached to a role object utilizing the Role Object Pattern (ROP). However, ROP itself does not contain a context definition and context-specific role assignment grouping the definition of smart contract relationships in abstracted data types. In this study, we would like to implement an extended version of the role object pattern called Context-based Role Object Pattern (ContextROP) with an onchain smart contract language called Solidity to solve fundamental problems. To evaluate the proposal, we will implement a use case with the design pattern proceeding with qualitative and quantitative analysis.