Testing and Comparing Value-at-Risk Measures in the Bulgarian Stock Market

The purpose of this thesis is to compare commonly used Value-at-Risk measures calculated through Historical and Monte Carlo Simulations and to answer the question whether these measures adequately capture market risk in EU new member country. Data set of daily returns price for ten years period from 24 October 2000 to 30 April 2010 was collected for the following market indices: SOFIX, S&P 500, NASDAQ, OMXS, FTSE 100 and DAX, to give representative overview of the developed world markets and compare them with the new EU member state Bulgaria. The behaviour of Value-at-Risk models with 99 % and 95 % confidence level using rolling data windows of 100 and 250 days is analyzed with the help of a range of backtesting procedures. Employed tests revealed that the distribution of daily returns of SOFIX index differs significantly from the Normal distribution, with high kutosis and large negative skewness. Highest Value-at-Risk violation levels were observed during periods with steep volatility jumps, which indicate that the measure reacts poorly to volatility changes and underestimate risk in turbulent market conditions. Based on the backtesting results it can be derived that VaR models that are commonly used in developed stock markets are not well suited for measuring market risk in EU new member states.fi=Opinnäytetyö kokotekstinä PDF-muodossa.|en=Thesis fulltext in PDF format.|sv=Lärdomsprov tillgängligt som fulltext i PDF-format

Risks and Prospects of Smart Electric Grids Systems measured with Real Options

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The economics of additive manufacturing and topology optimisation – a case analysis of the electric scooter

This article describes the process of topology optimisation (TO) of three components of an electric scooter, namely the neck, platform, and suspension bracket. We use these example parts to investigate the additive manufacturing (AM) workflow, from re-design to nesting and support approach that has an impact on the total costs and time required for product development and manufacturing, with a focus on Direct Metal Laser Sintering (DMLS) technology. Due to the mathematically generated shape, components that are topology optimised and fabricated through AM have improved structural load-to-weight ratio. The article elaborates on the cost of manufacturing these new geometrical structures and re-designing existing components. Recognising topology-optimised design features for the LPBF manufacturing process like creating touch points between parts in 3D nesting orientations and lattice structure integration reduces cost in volume production. Our study shows that it is beneficial for the DMLS process to perform finite element analysis (FEA) and optimise components using TO and lattice structures, as weight reduction also translates to cheaper fabricating parts. Defining and implementing a streamlined workflow for editing the complex automatically generated support structures improves manufacturability. Such approaches encourage companies to adopt wider LPBF processes in mainstream industries.© 2023 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.The terms on which this article has been published allow the posting of the Accepted Manuscript in a repository by the author(s) or with their consent.fi=vertaisarvioitu|en=peerReviewed

Towards a complex geometry manufacturing : A case study on metal 3D printing of topology optimised bicycle parts with lattices

Manufacturing metal parts with complex geometries using conventional methods has proven to be almost impossible due to tooling constraints. Additive Manufacturing (AM) or 3D printing has proven to be a solution for manufacturing such parts since the constraints imposed by traditional manufacturing are not applicable to AM. The research objective is to demonstrate the workflow from design to manufacturing complex geometry parts specifically for AM Selective Laser Melting (SLM) process, it also has its own constraints that are different than traditional manufacturing. AM provides a solution to manufacturing topology optimised complex geometries that cannot be manufactured using conventional methods. In order to demonstrate the possibilities and challenges of producing complex geometries with additive manufacturing, a case study of manufacturing topology optimised bicycle parts has been conducted at the University of Vaasa, Finland using SLM technology, based on the Powder Bed Fusion (PBF) process. The results of this research show that metal 3D printing is an enabler for manufacturing topology optimised complex geometries with challenges such as the need to edit and optimise the automatically-generated supports, and thermal solid support design for anchoring large flat surfaces, and possible boundary shells issues and post-processing planning.©2022 the Authors. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0/)fi=vertaisarvioitu|en=peerReviewed

Digital factory – virtual reality environments for industrial training and maintenance

This study evaluates the use of virtual reality (VR) platforms, which is an integrated part of the digital factory for an industrial training and maintenance system. The digital factory-based VR platform provides an intuitive and immersive human–computer interface, which can be an efficient tool for industrial training and maintenance services. The outcomes from this study suggested that use of the VR platform for training and maintenance of complex industrial tasks should be encouraged and use of the VR platform for that purpose should be further evaluated. This paper highlighted the generic concept of the application of virtual reality technique within the digital factory to industrial maintenance and to build a low-cost VR application for a training and maintenance system. An application case on virtual reality technique in a power plant operations and maintenance is demonstrated within the scope of this research. Overall research implications on virtual reality concept in industrial applications are concluded with future research directions.fi=vertaisarvioitu|en=peerReviewed

Cloud-Based Architecture for Production Information Exchange in European Micro-Factory Context

In a constantly changing world, information stands as one of the most valuable assets for a manufacturing site. However, exchanging information is not a straightforward process among factories, and concerns regarding the trustability and validation of transactions between various stakeholders have emerged within the context of micro-factories. This work presents an architecture designed to enable information exchange among heterogeneous stakeholders, taking advantage of the cloud infrastructure. It was designed to enable the use of several tools, connected through a middleware system deployed on the cloud. To demonstrate the potential of this architecture, a platform was instantiated, and two use cases—designed to accurately represent real manufacturing sites—were implemented.© 2023 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).fi=vertaisarvioitu|en=peerReviewed

PELAKSANAAN PENYIDIKAN TINDAK PIDANA CUKAI ROKOK OLEH SATUAN RESERSE KRIMINAL POLRES SOLOK

Tindak pidana merupakan gejala sosial yang akan dihadapi masyarakat bahkan negara. Salah satunya adalah tindak pidana cukai yaitu penyelewengan cukai. Mengenai tindak pidana Cukai ini telah diatur dalam Undang-Undang Nomor 39 Tahun 2007 tentang Cukai. Pada Pasal 1 Undang-Undang Nomor 39 tahun 2007 pengertian cukai adalah “pungutan Negara yang dikenakan terhadap barang-barang tertentu yang mempunyai sifat atau karakteristik yang ditetapkan dalam undang-undang ini”.Dalam hal ini cukai merupakan suatu pendapatan negara yang cukup besar dalam pembangunan nasional yang mana dalam pelanggarannya sangat merugikan negara. Untuk itu perlu adanya penanggulangan terhadap tindak pidana cukai yang dilakukan oleh penegak hukum yaitu dari pihak kepolisian sehingga terciptanya pembangunan nasional yang lancar. Permasalahan yang dibahas dalam Skripsi ini adalah (a) pelaksanaan penyidikan tindak pidana cukairokok, (b) kendala – kendala yang dihadapi oleh penyidik dalam pelaksanaan penyidikan tindak pidana cukai rokok dan (c) upaya yang dilakukan oleh penyidik dalam mengatasi kendala – kendala dalam pelaksanaan penyidikan tindak pidana cukai rokok oleh Satreskrim Polres Solok. Penelitian ini merupakan penelitian yang bersifat deskriptif, yaitu suatu penelitian yang menggambarkan atau menjelaskan dan memaparkan hasil dari penelitian secara deskriptif. Metode pendekatan yang digunakan dalam penelitian ini adalah metode pendekatan secara yudiris sosiologis. Sumber data adalah data primer dan data sekunder yang diperoleh dilapangan.Upaya – upaya yang dilakukan penyidik dalam mengatasi kendala – kendala yang dihadapi dalam penyidikan tindak pidana cukai rokok oleh Satreskrim Polres Solok, (a) pelatihan khusus bagi penyidik dalam menghadapi kasus tindak pidana cukai rokok. (b) memberikan penghargaan dan memberikan perlindungan hukum terhadap saksi yang terlibat dalam penyidikan tindak pidana cukai rokok. Kata kunci: Penyelewengan Cukai Roko

Blockchain-Based Supply Chain System in Automotive Industry for Small-and Medium-Sized Manufacturing

Blockchain technology enables a single database source to maintain permanent information about products and manufacturers and share transparent data in the supply chain from suppliers, factories, and distributors. In the automotive industry, blockchain technology has improved the transparency of the value chain and improved the operational efficiency of the supply chain. This research designed a blockchain-based supply chain system framework to meet the business needs of the automotive industry and improve operational performance. This research is based on the ongoing European Union Horizon 2020 project AVANGARD. The features of blockchain are investigated and aligned concerning SCM in the automotive industry.©2022 Springer. This is a post-peer-review, pre-copyedit version of an article published in Blockchain Driven Supply Chains and Enterprise Information Systems. The final authenticated version is available online at: https://doi.org/10.1007/978-3-030-96154-1_8.fi=vertaisarvioitu|en=peerReviewed

Cloud manufacturing ecosystem analysis and design

The manufacturing industry is facing the impact of a dynamic market and intensive competition. Many companies are looking for a new approach to improve their business activities in a collaborative business ecosystem with other stakeholders. Cloud computing enables the sharing of manufacturing resources and capabilities between different stakeholders to support business and physical production. The purpose of this research is to explore approaches moving towards a cloud manufacturing ecosystem and present possible implications for practice. To fulfil the research objectives, a multiple-case study was conducted within sheet metal manufacturing companies. Business and technology related requirements for cloud-based collaborative manufacturing portals were collected through interviews with industrial practitioners from the sheet metal manufacturing perspective. Based on analysis a prototype model of a CloudEcosystem was presented to demonstrate the essential features of the portals. This research found that there are three different portal types for cloud manufacturing ecosystems depending on the value chain configuration. Close to real-time information provided by cloud-based platforms can create manufacturing ecosystems where machine owners, product designers and customers may collaborate and compete simultaneously. The CloudEcosystem designed in this research can provide a practical tool and technical solution to help manufacturers think about moving towards cloud manufacturing ecosystems.©2021 Elsevier. This manuscript version is made available under the Creative Commons Attribution–NonCommercial–NoDerivatives 4.0 International (CC BY–NC–ND 4.0) license, https://creativecommons.org/licenses/by-nc-nd/4.0/fi=vertaisarvioitu|en=peerReviewed