• Fast Technical Introduction to Ethereum

    OK!Thess

    In this meetup we will do a technical introduction to Ethereum. This is *not* a high-level be-impressed-by-the-potential of smart contracts and Ethereum. It is intented for people who already understand how a blockchain, like Bitcoin, works. While it does not cover Ethereum in-depth, it will provide a fast technical introduction and identify key differences with other blockchains. The agenda for the meetup is: 19.00 - 20.00 Introduction to Ethereum: quick and technical 20.00 - 20.15 Break 20.15 - 21.15 Interacting with a node and a trivial smart contract 21.15 - 21.45 Open Q&A / Discussion / networking / end Abstracts: - Introduction to Ethereum: quick and technical This is *not* a high-level be-impressed-by-the-potential of smart contracts and Ethereum. It is intented for people who already understand how a blockchain, like Bitcoin, works. While it does not cover Ethereum in-depth, it will provide an fast technical introduction and identify key differences with other blockchains. - Interacting with a node and a trivial smart contract Going through the creation of a smart contract and its life-cycle. Short Biographies of presenters: Kostas Karasavvas Dr. Konstantinos Karasavvas is a computer scientist with 20+ years of experience. He has worked in academic research in multi-agent systems and service-oriented architectures for about a decade and following that he worked in the industry as a software architect and engineer for several years and in several domains; from bioinformatics to finance. Currently, and for the last 6 years, he is focused solely on blockchain technologies as a consultant. He is teaching and leading several research and development teams in both academia and industry. He is also an open source contributor and an active member of local Bitcoin communities, organizing meetups and presenting in events. --- The environment is casual and there will be plenty of opportunities to learn and more importantly get to know each other. After the event everyone is welcome to one of the nearby cafeterias to get to know each other. Hope to see you there!

  • 25th Blockchain meetup: The EOS Platform

    OK!Thess

    In this meetup the ComeTogether team (https://cometogether.network/) is going to introduce EOS to us. The agenda for the meetup is: 19.00 - 20.00 Introduction to EOS 20.00 - 20.15 Break 20.15 - 21.15 Example EOS Application 21.15 - 21.30 Discussion / networking / end Abstracts: Introduction to EOS The audience is going to be introduced to the basic concepts and characteristics of the EOS platform. It will go through how scalable EOS is (explaining the consensus algorithm), as well as it's governance and token model. Example EOS Application The ComeTogether EOS protocol/app is going to be discussed. From design decisions to implementation the audience will get an idea of how to go through the process of implementing an app in EOS. A demonstration of the app is going to conclude the talk. Short Biographies of presenters: Lazaros Penteridis (Founder/CEO) Former AI and Robotics software engineer for 3 years. Has developed cloud robotics solutions, for clients such as Ericsson. MSc in Electrical and Computer Engineering from Aristotle University of Thessaloniki (AUTH). Stavros Antoniadis (Co-Founder/Blockchain engineer) Deep into smart contract development and cryptoeconomics. Formerly, mobile developer and test automation engineer at Schoox Inc. Final year student in Electrical and Computer Engineering, AUTH. Nikos Chatzivasileiadis (Co-Founder/Full stack engineer) Wide spectrum of software skills. Formerly, web developer intern at Veltio Greece Ltd. Final year student in Electrical and Computer Engineering, AUTH. Stathis Mitskas (Co-Founder/Full stack engineer) Has acquired three master degrees (CS, Finance-Banking, Leadership), two of which at the University of Bristol. Has been awarded the best paper on the 1st Workshop on Blockchain-enabled Networked Sensor Systems (BlockSys 2018). The environment is casual and there will be plenty of opportunities to learn and more importantly get to know each other. After the event everyone is welcome to one of the nearby cafeterias to get to know each other. Hope to see you there!

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  • Cryptocurrency Social meeting (last of 2018)

    Κοινωνική συνάντηση στο crypto-friendly μαγαζί "Dastart" (http://www.dastart.com -- στον πάνω όροφο) για να "τα πούμε" μια τελευταία φορά πριν το νέο έτος ! Social meetup at "Dastart" (http://www.dastart.com -- upstairs) to get to hang out one last time before the New Year! Hope to see you there! And Merry Christmas to everyone !!

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  • Cryptocurrencies: Basics of Technical Analysis and Trading

    This meetup is focused on cryptocurrency trading and technical analysis. Some basic theory and demonstrations will be provided between the two talks. IMPORTANT: Under no circumstances should anything mentioned in the meetup be considered trading or financial advice! The agenda for the meetup is: 19.00 - 20.00 Introduction to Technical Analysis — Monis Chagouel 20.00 - 20.15 Break 20.15 - 21.15 Long Term View of Bitcoin and Alt coins price action — Androklis Polymenis 21.15 - 21.30 Discussion / networking / end Abstracts: - Introduction to Technical Analysis An overview on basic Technical Analysis terms and Japanese candlestick charting techniques. Identifying supports, resistances, drawing trend-lines and fibonacci retracement etc. - Long Term View of Bitcoin and Alt coins price action Using Point & Figure to determine: 1) Patterns 2) Supports/Resistances 3) Price Objectives $BTC is acting for the crypto market like SP500 for stock market Bullish Percentage Indicator Short Biographies of presenters: - Monis has a masters in Banking & Finance and a Bachelor degree in Business Enterprise. He kicked off his career as an Equity sales trader and for the last 8 years he is an FX trader within a Corporate Treasury Function for a NASDAQ listed firm. His professional interests span the areas of valuation of EM & G10 FX and macro linkages across asset markets and his specialties are around FX trading, Technical Analysis and risk mitigation. He is an active member of the Bitcoin Cyprus Club, the founder of the Greek Cryptocurrency Community, an active telegram channel for Greek crypto enthusiasts. He is deeply interested in fundamental analysis and network fair value metrics, smart contracts and blockchain technologies that make a positive change. - Androklis is a cryptocurrency entrepreneur, technical analysis expert and software engineer in Greece. He is the founder of CryptXO and UbiCrypt companies which specialize in cryptoassets-related consulting services, providing expert fundamental and technical analysis. Best known in the cryptocurrency community as “kLee”, Mr. Polymenis is a Bitcoin early adopter, entering this field in 2011, and one of the 73 original stakeholders of NXT (http://nxtcrypto.org/#). He is also participating on new and exciting crypto-related projects in an advisory role, among which he is actively involved in the Thought AI project (https://thought.live/), MOBS Video Marketplace (https://mobs.video/) and he was involved in the earlier stages of TomoChain (https://tomochain.com/). The environment is casual and there will be plenty of opportunities to learn and more importantly get to know each other. After the event everyone is welcome to one of the nearby cafeterias to get to know each other. Hope to see you there!

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  • Ethereum Plasma and Bitcoin Scripting

    OK!Thess

    First an announcement: On 19-20 of November the next Voxxed Days developer conference will take place in Thessaloniki! This is a very successful and high-profile conference for developers and is taking place at our home town! You will find more information at http://thessaloniki.voxxeddays.com They were kind enough to offer free tickets for the members of our meetup. During the break we will make a draw and two lucky members will be able to attend the conference for free. The agenda for the meetup is: 19.00 - 20.00 Introduction to Plasma for Blockchain Scalability — Georgios Konstantopoulos 20.00 - 20.15 Break 20.15 - 21.15 Introduction to Bitcoin Scripting — Kostas Karasavvas 21.15 - 21.30 Discussion / networking / end Abstracts: - Introduction to Plasma for Blockchain Scalability Plasma is a technique which is used to increase Ethereum transaction throughput, while maintaining network decentralization and security. We focus on the variant of Plasma called Plasma Cash, which allows for highly performant sidechains in production, today. We discuss Plasma Exits and Challenges as well as explore the User Interface choices for Plasma Apps. We go over the challenges encountered during the development and final implementation of a Plasma chain and contract. The presentation will highlight the advantages and disadvantages of using Plasma Cash, as well as practical examples of Plasma for Non Fungible Tokens and gaming. Finally, we'll talk about edge-cases such as griefing attacks, and future work towards making Plasma implementations more efficient, such as fast exits through liquidity providers, coin checkpointing through Plasma XT and arbitrary coin denominations through Plasma Debit. The audience is expected to walk away with a detailed understanding of how Plasma Chains should be built as well as the inner workings of the Plasma Cash technique. More experienced individuals who understand but are not following Plasma actively are expected to walk away with an overview of the current status of Plasma research and development, and motivated to tackle the existing open research problems. - Introduction to Bitcoin Scripting In this talk we go deeper into what constitutes a transaction and how scripting is used to lock bitcoins and later unlock them to spend them. We then provide several examples on how to create transactions by calling a node’s API or programmatically. Short Biographies of presenters: - Georgios is leading Plasma Research at Loom Network. He holds a MEng degree in Electrical & Computer Engineering. He previously worked at Honda where he did his thesis on metering and billing of energy with smart contracts. He has also worked as an independent smart contract auditor and pentester. He is interested in all-things-blockchain as well as cryptography, IoT, infosec and autonomous vehicles. - Dr. Konstantinos Karasavvas is a computer scientist with 20+ years of experience. He has worked in academic research in multi-agent systems and service-oriented architectures for about a decade and following that he worked in the industry as a software architect and engineer for several years and in several domains from bioinformatics to finance. Currently, and for the last 5 years, he is focused solely on blockchain technologies as a technical advisor. He is teaching and leading several research and development teams in both academia and industry. He is also an active member of local Bitcoin communities, organizing meetups and presenting in events. The environment is casual and there will be plenty of opportunities to learn and more importantly get to know each other. After the event everyone is welcome to one of the nearby cafeterias to get to know each other. Hope to see you there!

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  • Blockchain Consensus and Bitcoin's SPV

    OK!Thess

    First an announcement: On 14-16 of November the next Decentralized conference will take place in Athens. The first Decentralized conference in Cyprus was very successful and this one is expected to be even better. You will find more information at https://www.decentralized.com/ They were kind enough to offer us free tickets for the members of the meetup. During the break we will make a draw and two lucky members will be able to attend the conference for free. The agenda for the meetup is: 19.00 - 19.45 Consensus Algorithms — Thomas Sermpinis 19.45 - 20.15 Break 20.15 - 21.00 Simplified Payment Verification in Bitcoin — George Vlahavas 21.00 - 21.30 Discussion / networking / end Abstracts: - Consensus Algorithms Bitcoin and especially blockchain technologies presented a new era of decentralization, and the need for methods to reach consensus became imperative. Because of that, several consensus algorithms were developed and used by blockchains and cryptocurrencies, in order to secure these networks, but none of them is perfect and each of them has its strengths. In this presentation we will discuss several consensus algorithms, which are widely used by decentralized technologies. - Simplified Payment Verification in Bitcoin Description of how SPV wallets work in Bitcoin and the reasons why SPV is needed for lightweight clients. Transaction verification with SPV clients. Security and privacy issues. Bloom filters and their use in SPV clients. Short Biographies of presenters: - Thomas Sermpinis is a security and blockchain engineer with a Masters Degree in Informatics and Management. He has worked as an instructor in the field of cyber security, covering a wide variety of topics. Also, he is deeply involved in the cyber security community, with a strong social media presence (security blog and popular YouTube channel). For the last year he is dedicated to blockchain technology and currently works as a blockchain research engineer in Aristotle University. - George Vlahavas is a PhD candidate and researcher in the Department of Informatics, Aristotle University of Thessaloniki. He has extensive experience developing open source software and has been actively involved in the Linux community, both at a local and global level. He is the founder and project lead of Salix (www.salixos.org), a GNU/Linux distribution based on Slackware that is simple, fast and easy to use, with stability being the primary goal. His current research interests are focused on blockchain technologies. The environment is casual and there will be plenty of opportunities to learn and more importantly get to know each other. After the event everyone is welcome to one of the nearby cafeterias to get to know each other. Hope to see you there!

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  • Blockchain meets Machine Learning: Joint Meetup

    The agenda for the meetup is: 19.00 - 19.45 Introduction to Bitcoin and Blockchain — Thomas Sermpinis 19.45 - 20.00 Break 20.00 - 20.15 Introduction to Machine Learning — Nikolaos Passalis 20.15 - 21.15 Discussion of Bitcoin price prediction using Deep Learning Models — Avraam Tsantekidis 21.15 - 21.30 Discussion / networking / end Please note that presentations will be in Greek. Abstracts: - Introduction to Bitcoin and Blockchain Bitcoin and especially blockchain technologies get more and more important each day, breaking the barrier of the cryptocurrency with the introduction of many new practical applications. In this presentation we will discuss the fundamentals of blockchain technologies, using Bitcoin as our benchmark, and covering topics like transactions, nodes, consensus and other important aspects of these technologies. - Introduction to Machine Learning Nikolaos Passalis will present and refresh the most important Machine Learning and Deep Learning concepts, along with some applications using the well-known Keras library, in less than 15 minutes. Some familiarity with Python is all you need! - Discussion of Bitcoin price prediction using Deep Learning Models Lately Bitcoin has been receiving more and more attention, both as a technological achievement capable of allowing true ownership of ones' wealth, but also as a risky investment opportunity which has attracted a significant amount of capital. There are many faucets of Bitcoin and Blockchain technology upon which Machine Learning can be applied and yield practical results. In this presentation, the topic of Bitcoin price prediction using Deep Learning models, such Long-Short Term Memory (LSTM) networks, will be discussed. Several code examples using Python and Keras, backed by Tensorflow, will be presented, walking you through all the necessary steps to understand the basics of building a Machine Learning model and testing it on real financial data. Short Biographies of presenters: - Thomas Sermpinis is a security and blockchain engineer with a Masters Degree in Informatics and Management. He has worked as an instructor in the field of cyber security, covering a wide variety of topics. Also, he is deeply involved in the cyber security community, with a strong social media presence (security blog and popular YouTube channel). For the last year he is dedicated to blockchain technology and currently works as a blockchain research engineer in Aristotle University. - Nikolaos Passalis is a Ph.D. candidate and researcher in the Department of Informatics, Aristotle University of Thessaloniki. He obtained his B.Sc. in Informatics in 2013 and his M.Sc. in Information Systems in 2015 from Aristotle University of Thessaloniki, Greece. His research interests include deep learning, computational intelligence and information retrieval. His doctoral studies are supported by the General Secretariat for Research and Technology (GSRT) and the Hellenic Foundation for Research and Innovation (HFRI). - Avraam Tsantekidis is a Ph.D. candidate in the Artificial Intelligence & Information Analysis Laboratory of the Department of Informatics, Aristotle University of Thessaloniki. He obtained his B.Sc. in Informatics in 2016 from the Aristotle University of Thessaloniki. His research interests include Deep Learning, Time Series and Financial Markets. During the first year of his Ph.D. he was employed by an Investment Fund to research and develop Deep Learning to support its financial activities. The environment is casual and there will be plenty of opportunities to learn and more importantly get to know each other. After the event everyone is welcome to one of the nearby cafeterias to get to know each other. Hope to see you there!

  • Blockchain and .NET Joint meetup: NEO

    OK!Thess

    Το πρόγραμμα της συνάντησης θα είναι: 19.00 - 19.45 Εισαγωγή στη blockchain τεχνολογία και στo NEO project — Δημήτρης Σφούνης 19.45 - 20.00 Διάλειμμα (δικτύωση / γνωριμίες) 20.00 - 21.00 Συμβόλαια ΝΕΟ σε C# — Δημήτρης Σφούνης 21.00 - 21.30 Συζήτηση / δικτύωση / τέλος Παρουσίαση του NEO σε δύο μέρη. Στο πρώτο Θα έχουμε μία εισαγωγή στην τεχνολογία του blockchain και πιο ειδικά στην πλατφόρμα του ΝΕΟ και στο δεύτερο μέρος μια παρουσίαση για το πως μπορεί να γράψει κάποιος έξυπνα συμβόλαια χρησιμοποιόντας C#: παράδειγμα συμβολαίου και ο κύκλος ζωής του κώδικα. Το περιβάλλον είναι χαλαρό και θα υπάρχουν πολλές ευκαιρίες για να μάθουμε και φυσικά για να γνωριστούμε. Μετά τις παρουσιάσεις είναι όλοι ευπρόσδεκτοι σε κάποια από τις κοντινές καφετέριες που πάμε για να γνωριστούμε καλύτερα. Ελπίζω να σας δω στη συνάντηση! Αφίσα εκδήλωσης: ********************* The agenda for the meetup is: 19.00 - 19.45 Introduction to Blockchain and the NEO project — Dimitris Sfounis 19.45 - 20.00 Break 20.00 - 21.00 NEO contracts in C# — Dimitris Sfounis 21.00 - 21.30 Discussion / networking / end A two part presentation on the NEO platform. In the first part Dimitris Sfounis will introduce some fundamentals on blockchain technology and particularly the NEO platform and in the second he will present how to write smart contracts using C#: writing a contract and its lifecycle. The environment is casual and there will be plenty of opportunities to learn and more importantly get to know each other. After the event everyone is welcome to one of the nearby cafeterias to get to know each other. Hope to see you there! Event flyer:

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  • Blockchain and Python Joint meetup: Ethereum

    Το πρόγραμμα της συνάντησης θα είναι: 20.00 - 20.50 Εισαγωγή στο Ethereum — Γιώργος Κωνσταντόπουλος 20.50 - 21.00 Διάλειμμα (δικτύωση / γνωριμίες) 21.00 - 21.50 Solidity με παραδείγματα (+Python) — Γιώργος Κωνσταντόπουλος 21.50 - 22.15 Συζήτηση / δικτύωση / τέλος Παρουσίαση του Ethereum σε δύο μέρη. Στο πρώτο Θα έχουμε μία εισαγωγή στο Ethereum και σε αποκεντρωμένες εφαρμογές και στο δεύτερο μέρος μια παρουσίαση για τη γλώσσα Solidity, γράφοντας έξυπνα συμβόλαια και ο κύκλος ζωής τους όπως και έξτρα παραδείγματα συμβολαίων. Το περιβάλλον είναι χαλαρό και θα υπάρχουν πολλές ευκαιρίες για να μάθουμε και φυσικά για να γνωριστούμε. Ελπίζω να σας δω στη συνάντηση! **************** The agenda for the meetup is: 20.00 - 20.50 Introduction to Ethereum — George Konstantopoulos 20.50 - 21.00 Break 21.00 - 21.50 Solidity by Examples (+Python) — George Konstantopoulos 21.50 - 22.15 Discussion / networking / end A two part presentation on the Ethereum platform. In the first part George will introduce Ethereum and Decentralized Applications and in the second he will present the solidity language, writing a contract and its lifecycle as well as more contract examples. The environment is casual and there will be plenty of opportunities to learn and more importantly get to know each other. Hope to see you there!

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  • 17th Meetup: Introduction to IOTA

    OK!Thess

    • What we'll do Το πρόγραμμα για την 17η συνάντηση θα είναι: 19.00 - 20.00 Εισαγωγή στο IOTA — Χρήστος Δουκάκης 20.00 - 20.15 Διάλειμμα (δικτύωση / γνωριμίες) 20.15 - 21.00 e-Puzzles και Bitcoin — Κώστας Καρασάββας 21.00 - 21.30 Συζήτηση / δικτύωση / τέλος Θα έχουμε μία εισαγωγή στο ΙΟΤΑ από προγραμματιστή του ίδιου του project. Θα συζητηθεί το πως λειτουργεί, τί είναι το "tangle" και τι προσφέρει όπως επίσης και πως διαφοροποιείται από την blockchain τεχνολογία. Η δεύτερη παρουσίαση θα έχει κάποια ενδιαφέροντα trivia και puzzles σχετικά με το Bitcoin. Το περιβάλλον είναι χαλαρό και θα υπάρχουν πολλές ευκαιρίες για να μάθουμε και φυσικά για να γνωριστούμε. Ελπίζω να σας δω στη συνάντηση! *************** The agenda for the 17th meetup is: 19.00 - 20.00 Introduction to IOTA — Chris Dukakis 20.00 - 20.15 Break (networking) 20.15 - 21.00 e-Puzzles and Bitcoin — Kostas Karasavvas 21.00 - 21.30 Discussion / networking / end An introduction to IOTA by Chris Dukakis a core developer of the project. A discussion on how it works, what the "tangle" is and what it offers as well as how it differs from blockchain technology. The environment is casual and there will be plenty of opportunities to learn and more importantly get to know each other. The second presentation will introduce some interesting trivia and puzzles regarding Bitcoin. Hope to see you there!

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