The document provides an overview of Solidity data structures including basic value types like integers, booleans, addresses, fixed point numbers and bytes. It also covers arrays, structs, mappings and how to interact with them from Solidity. Additionally, it discusses the Ethereum development tools and frameworks needed like Ganache, Truffle, web3 and how to deploy contracts to a test network like Kovan.
“Create your own cryptocurrency in an hour” - Sandip PandeyEIT Digital Alumni
Blockchain has already started disrupting or improving several industries with innovative solutions impacting our lives in more ways than we could have ever imagined. One such application of blockchain is a cryptocurrency. In this workshop, we create a simple cryptocurrency based on smart contracts, and talk about a few best practises on writing secure smart contracts to get you started with developing decentralized applications.
Ethereum is by far the most common contract platform on top of which a variety of application are running. One of the well-accepted application is Token. Token is implemented through a token contract. Here we introduce the ERC20 standard and see more in detail on an ERC20 Token Contract.
Bob Tiernay explores the fascinating world of jq, "the JSON Processor”. Starting with a motivation, he then covers the language, provides helpful tips, showcases a real world example, cautions some things to avoid and finishes with a discussion of the ecosystem.
Principais vulnerabilidades em Smart Contracts e como evitá-lasJúlio Campos
Smart contracts são tendência em diversas áreas. São fáceis de criar e de se colocar no ar, mas a principal linguagem utilizada e seu compilador (Solidity) não protegem os contratos. Erros de estouro de pilha podem ocorrer e você perder todos seus ativos. Nesta palestra veremos os principais pontos de ataque e como evitá-las.
JSON is a well-known, lightweight format for data exchange around the web. It’s a structured data format used in modern APIs and goes really well with web applications. But how do you work with these JSON files directly and perform operations on it? This is where JQ comes into play.
JQ is a flexible, lightweight, command-line processor that is like ‘sed’ for JSON data. JQ gets along well with UNIX pipes and offers rich functionality to interrogate, manipulate, and work with JSON files.
In this webinar, you will be introduced to JQ and you will learn how to work with basic filters, operators & functions, conditionals & comparisons. You will also learn how to define functions, work with Regex, and use streaming JSON data in JQ.
Blockchain , Deploying your first smart contract to azure ethereum blockchain.
Slides from my session in "Global Azure Bootcamp Chandigarh"
Presentation starts with basic terms like transactions , ledger and contracts. Talks about what is blockchain and ethereum and concludes with deployment of a smart contract to azure ethereum blockchain.
Red Hat Forum Tokyo - OpenStack ArchitectureDan Radez
This was presented at the Red Hat Forum in Tokyo, November 2012. It's a basic getting started with OpenStack using RDO. It's the same as the OpenStack meetups presentation from November 2012
“Create your own cryptocurrency in an hour” - Sandip PandeyEIT Digital Alumni
Blockchain has already started disrupting or improving several industries with innovative solutions impacting our lives in more ways than we could have ever imagined. One such application of blockchain is a cryptocurrency. In this workshop, we create a simple cryptocurrency based on smart contracts, and talk about a few best practises on writing secure smart contracts to get you started with developing decentralized applications.
Ethereum is by far the most common contract platform on top of which a variety of application are running. One of the well-accepted application is Token. Token is implemented through a token contract. Here we introduce the ERC20 standard and see more in detail on an ERC20 Token Contract.
Bob Tiernay explores the fascinating world of jq, "the JSON Processor”. Starting with a motivation, he then covers the language, provides helpful tips, showcases a real world example, cautions some things to avoid and finishes with a discussion of the ecosystem.
Principais vulnerabilidades em Smart Contracts e como evitá-lasJúlio Campos
Smart contracts são tendência em diversas áreas. São fáceis de criar e de se colocar no ar, mas a principal linguagem utilizada e seu compilador (Solidity) não protegem os contratos. Erros de estouro de pilha podem ocorrer e você perder todos seus ativos. Nesta palestra veremos os principais pontos de ataque e como evitá-las.
JSON is a well-known, lightweight format for data exchange around the web. It’s a structured data format used in modern APIs and goes really well with web applications. But how do you work with these JSON files directly and perform operations on it? This is where JQ comes into play.
JQ is a flexible, lightweight, command-line processor that is like ‘sed’ for JSON data. JQ gets along well with UNIX pipes and offers rich functionality to interrogate, manipulate, and work with JSON files.
In this webinar, you will be introduced to JQ and you will learn how to work with basic filters, operators & functions, conditionals & comparisons. You will also learn how to define functions, work with Regex, and use streaming JSON data in JQ.
Blockchain , Deploying your first smart contract to azure ethereum blockchain.
Slides from my session in "Global Azure Bootcamp Chandigarh"
Presentation starts with basic terms like transactions , ledger and contracts. Talks about what is blockchain and ethereum and concludes with deployment of a smart contract to azure ethereum blockchain.
Red Hat Forum Tokyo - OpenStack ArchitectureDan Radez
This was presented at the Red Hat Forum in Tokyo, November 2012. It's a basic getting started with OpenStack using RDO. It's the same as the OpenStack meetups presentation from November 2012
A Decompiler for Blackhain-Based Smart Contracts BytecodeShakacon
Ethereum is gaining a significant popularity in the blockchain community, mainly due to fact that it is design in a way that enables developers to write decentralized applications (Dapps) and smart-contract using blockchain technology.
Ethereum blockchain is a consensus-based globally executed virtual machine, also referred as Ethereum Virtual Machine (EVM) by implemented its own micro-kernel supporting a handful number of instructions, its own stack, memory and storage. This enables the radical new concept of distributed applications.
Contracts live on the blockchain in an Ethereum-specific binary format (EVM bytecode). However, contracts are typically written in some high-level language such as Solidity and then compiled into byte code to be uploaded on the blockchain. Solidity is a contract-oriented, high-level language whose syntax is similar to that of JavaScript.
This new paradigm of applications opens the door to many possibilities and opportunities. Blockchain is often referred as secure by design, but now that blockchains can embed applications this raise multiple questions regarding architecture, design, attack vectors and patch deployments.
As we, reverse engineers, know having access to source code is often a luxury. Hence, the need for an open-source tool like Porosity: decompiler for EVM bytecode into readable Solidity-syntax contracts – to enable static and dynamic analysis of compiled contracts but also vulnerability discovery.
Managing Large-scale Networks with Triggerjathanism
Trigger was designed to increase the speed and efficiency of managing network configuration while reducing human error, and is the bread and butter of how we manage the large-scale network at AOL. In this talk I intend to cover the problems we solved using Python to manage our network infrastructure, especially how each network vendor does things distinctly differently, and about the code and API that makes Trigger tick using detailed examples.
Given at SCaLE 11x, Los Angeles, CA
Video: http://www.youtube.com/watch?v=7zZ9980X_bs
Scaling Ethereum using Zero-Knowledge ProofsHyojun Kim
Introduces the way how ZKPs can be used to scale Ethereum blockchains.
— What is Zero-Knowledge Proof?
— zk-SNARKs and Succinctness
— Layer-2 Scalability using zk-SNARKs
— Using SNARK on Ethereum
— Going Future: zk-STARKs
We're hiring! abr.ge/ueaerh
Athens IoT meetup #7 - Create the Internet of your Things - Laurent Ellerbach...Athens IoT Meetup
Laurent Ellerbach, technical evangelist manager at Microsoft, presentation of the "Internet of (his garden) Things", explaining the technical architecture details and decisions.
What is the promise of smart contracts? How is their development different from software engineering? What practices should one adopt if becoming a smart contracts engineer?
🚀 What Are GPTs?
GPTs are tailor-made ChatGPT versions that you can craft to suit your specific needs. Whether it's for learning new skills, aiding in education, or assisting in unique work tasks, these custom GPTs are designed to be versatile and incredibly user-friendly.
✨ Create Your Own AI Assistant - No Coding Required! The best part? You don't need to be a tech wizard to create your GPT. The process is as simple as starting a conversation - guiding the AI, feeding it extra knowledge, and choosing its capabilities, like web searching, crafting images, or data analysis.
Generative AI Use-cases for Enterprise - First SessionGene Leybzon
In this presentation, we will delve into the exciting applications of Generative AI across various business domains. Leveraging the capabilities of artificial intelligence and machine learning, Generative AI allows for dynamic, context-aware user interfaces that adapt in real-time to provide personalized user experiences. We will explore how this transformative technology can streamline design processes, facilitate user engagement, and open the doors to new forms of interactivity.
Non-fungible tokens (NFTs) are unique digital assets that are verified on a blockchain network, allowing for the creation and ownership of one-of-a-kind digital items, such as artwork, music, videos, and other types of digital content. They are important because they provide a way for digital creators to monetize their work and establish ownership, scarcity, and authenticity of their creations. NFTs have also gained popularity as a form of investment and collectible item, with some NFTs selling for millions of dollars.
This slide deck includes the following sections:
Introduction: Provide a brief overview of what NFTs are and their significance in the digital world.
How NFTs work: Explain the process of creating and verifying NFTs on a blockchain network, including the use of smart contracts and cryptographic hashing.
Types of NFTs: Describe the various types of NFTs that can be created, such as digital artwork, music, videos, and other types of digital content.
Benefits of NFTs: Highlight the benefits of NFTs, including the ability to establish ownership, scarcity, and authenticity of digital assets, as well as their potential as a new source of revenue for creators.
Market trends: Provide an overview of the current state of the NFT market, including recent sales and trends in various industries, such as art, sports, and gaming.
Potential use cases: Discuss potential use cases for NFTs beyond the current market, such as in the areas of identity verification, supply chain management, and digital voting.
Challenges and risks: Acknowledge the challenges and risks associated with NFTs, such as environmental concerns related to blockchain networks and the potential for fraudulent activity.
Conclusion: Summarize the key takeaways of the presentation and emphasize the growing importance of NFTs in the digital world.
Introduction to Solidity and Smart Contract Development (9).pptxGene Leybzon
Blockchain is a revolutionary technology that is changing the way we handle digital transactions. It is a technology that can be applied in many different fields, from logistics and supply chain management to real estate and voting systems.
In order to help our clients to plan and execute digital transformation, we need to understand foundational elements, including smart contracts and languages that are popular in developing smart contracts.
In this presentation, we share an overview of what a smart contract is and how it functions, look into the real-world examples of smart contracts, and tools that are used to develop smart contracts. We look into Solidity, a powerful programming language that enables developers to create complex and sophisticated smart contract applications on Ethereum-compatible blockchains.
There is no expectation of prior knowledge of blockchain technology or smart contracts development and we are expecting to have a lively and engaging session.
Ethereum and other blockchains are finding their way into the enterprise world. We look into common use cases, blockchains, and standard approaches to deploy and access enterprise blockchains
Smart contracts and NFTs call for a revised approach to store data. In these slides, 3 options for distributed and fault-tolerant data storage are presented:
IPFS
Filecoin
Arweave
Demonstrating how to create an end-to-end Web-based application that uses blockchain for user authentication, read, and write access to the data stored on the blockchain
Macroeconomics- Movie Location
This will be used as part of your Personal Professional Portfolio once graded.
Objective:
Prepare a presentation or a paper using research, basic comparative analysis, data organization and application of economic information. You will make an informed assessment of an economic climate outside of the United States to accomplish an entertainment industry objective.
Honest Reviews of Tim Han LMA Course Program.pptxtimhan337
Personal development courses are widely available today, with each one promising life-changing outcomes. Tim Han’s Life Mastery Achievers (LMA) Course has drawn a lot of interest. In addition to offering my frank assessment of Success Insider’s LMA Course, this piece examines the course’s effects via a variety of Tim Han LMA course reviews and Success Insider comments.
Francesca Gottschalk - How can education support child empowerment.pptxEduSkills OECD
Francesca Gottschalk from the OECD’s Centre for Educational Research and Innovation presents at the Ask an Expert Webinar: How can education support child empowerment?
How to Make a Field invisible in Odoo 17Celine George
It is possible to hide or invisible some fields in odoo. Commonly using “invisible” attribute in the field definition to invisible the fields. This slide will show how to make a field invisible in odoo 17.
Synthetic Fiber Construction in lab .pptxPavel ( NSTU)
Synthetic fiber production is a fascinating and complex field that blends chemistry, engineering, and environmental science. By understanding these aspects, students can gain a comprehensive view of synthetic fiber production, its impact on society and the environment, and the potential for future innovations. Synthetic fibers play a crucial role in modern society, impacting various aspects of daily life, industry, and the environment. ynthetic fibers are integral to modern life, offering a range of benefits from cost-effectiveness and versatility to innovative applications and performance characteristics. While they pose environmental challenges, ongoing research and development aim to create more sustainable and eco-friendly alternatives. Understanding the importance of synthetic fibers helps in appreciating their role in the economy, industry, and daily life, while also emphasizing the need for sustainable practices and innovation.
2024.06.01 Introducing a competency framework for languag learning materials ...Sandy Millin
http://sandymillin.wordpress.com/iateflwebinar2024
Published classroom materials form the basis of syllabuses, drive teacher professional development, and have a potentially huge influence on learners, teachers and education systems. All teachers also create their own materials, whether a few sentences on a blackboard, a highly-structured fully-realised online course, or anything in between. Despite this, the knowledge and skills needed to create effective language learning materials are rarely part of teacher training, and are mostly learnt by trial and error.
Knowledge and skills frameworks, generally called competency frameworks, for ELT teachers, trainers and managers have existed for a few years now. However, until I created one for my MA dissertation, there wasn’t one drawing together what we need to know and do to be able to effectively produce language learning materials.
This webinar will introduce you to my framework, highlighting the key competencies I identified from my research. It will also show how anybody involved in language teaching (any language, not just English!), teacher training, managing schools or developing language learning materials can benefit from using the framework.
Unit 8 - Information and Communication Technology (Paper I).pdfThiyagu K
This slides describes the basic concepts of ICT, basics of Email, Emerging Technology and Digital Initiatives in Education. This presentations aligns with the UGC Paper I syllabus.
The French Revolution, which began in 1789, was a period of radical social and political upheaval in France. It marked the decline of absolute monarchies, the rise of secular and democratic republics, and the eventual rise of Napoleon Bonaparte. This revolutionary period is crucial in understanding the transition from feudalism to modernity in Europe.
For more information, visit-www.vavaclasses.com
4. BASIC VALUE TYPES
Data Type Example
uint<M> , M=1,2,4, …, 256
int<M>, uint, int
Unsigned/signed integer uint256 counter = 1;
address 160-bit (20byte) value that
does not allow any
arithmetic operations. It is
suitable for storing
addresses of contracts or
keypairs belonging to
external persons.
Address has property
“balance”
address owner =
msg.sender;
If (owner.balance>10) …
bool Same as uint8 but values are
0 or 1
Bool b = 0;
b=true;
fixed<M>x<N>
ufixed<M>x<N>
Signed fixed-point decimal
number of M bits
fixed128x19 f = 1.1;
5. ARRAYS
Data Type Example
bytes1…bytes32, byte Fixed-size byte arrays byte1 bt1= 1;
Byte2 bt2=1;
if (bt2[0]==0) …
bt2.length
byte[N]
uint[N]
bool[N]
…
Fixed-size arrays byte[10] b;
fixed5x19[10] f;
byte[] Dynamic array uint[] memory a = new
uint[](7);
bytes Tightly-packed byte array bytes memory b = new
bytes(123);
string Same as bytes but can not string s=“Hello!”;
6. STRUCTS
pragma solidity ^0.4.11;
contract CrowdFunding {
// Defines a new type with two fields.
struct Funder {
address addr;
uint amount;
}
….
uint numFunders = 0;
mapping (uint => Funder) funders;
funders[numFunders++] = Funder({addr: msg.sender, amount: msg.value});
….
}
7. MAPPINGS
pragma solidity ^0.4.11;
contract CrowdFunding {
// Defines a new type with two fields.
struct Funder {
address addr;
uint amount;
}
….
uint numFunders = 0;
mapping (uint => Funder) funders;
funders[numFunders++] =
Funder({addr: msg.sender, amount: msg.value});
….
}
mapping(_KeyType => _ValueType)
_KeyType:
any type except mapping, dyn array,
contruct, enum or struct
_ValueType:
any type, including mappings
18. KOVAN TESTNET
Kovan is a Proof of Authority publicly accessible blockchain for
Ethereum; created and maintained by a consortium of Ethereum
developers, to aide the Ethereum developer community.
Connect Get KETH Develop
19. START PARITY AND CONNECT TO
KOVAN
•sudo parity --chain
kovan ui
Etherium
with
Kovan
20. CREATE ACCOUNT ON KOVAN
NETWORK
parity account new --chain kovan
[Remember password and account id]
[Store password in a file for later use]
22. GET SOME ETHER (STEP 1, ASK)
Icarus Faucet (Automated after SMS
Verification)
https://youtu.be/99UucFzYCRc OR
Gitter Channel
https://gitter.im/kovan-testnet/faucet OR
Ask Gene – add comment with your account id
to the message board on
https://www.meetup.com/Blockchain-
Applications-and-Smart-
Contracts/events/tzwnjpyxfbmc/
23. GET SOME ETHER (STEP 2, SYNC
WITH NETWORK)
sudo parity --chain kovan
24. GET SOME ETHER (STEP 3, CHECK
YOUR BALANCE)
sudo geth attach
<path>/io.parity.ethereum/jsonrpc.ipc
account list
>
web3.fromWei(eth.getBalance(eth.coinbas
e), "ether")
50
28. CREATE ERC20 COIN CONTRACT
(SOLIDITY CODE)pragma solidity ^0.4.4;
import "../node_modules/zeppelin-solidity/contracts/token/StandardToken.sol";
/**
* @title RespectCoin
* @dev ERC20 Token example, where all tokens are pre-assigned to th
e creator.
* Note they can later distribute these tokens as they wish using `transfer` and
other
* `StandardToken` functions.
*/
contract RespectCoin is StandardToken {
string public constant name = "RespectCoin";
string public constant symbol = "RESPECT";
uint8 public constant decimals = 18;
uint256 public constant INITIAL_SUPPLY = 10000 * (10 ** uint256(decimals));
/**
* @dev Constructor gives msg.sender all tokens
*/
function RespectCoin() public {
totalSupply = INITIAL_SUPPLY;
balances[msg.sender] = INITIAL_SUPPLY;
}
}
34. ERC223 TOKEN
ERC223 is backwards compatible with ERC20
merges the token transfer function among wallets and contracts into
one single function ‘transfer()’
does not allow token to be transferred to a contract that does not
allow token to be withdrawn
Improvements with ERC223
• Eliminates the problem of lost tokens which happens during the transfer of ERC20 tokens to a
contract (when people mistakenly use the instructions for sending tokens to a wallet). ERC223
allows users to send their tokens to either wallet or contract with the same function transfer,
thereby eliminating the potential for confusion and lost tokens.
• Allows developers to handle incoming token transactions, and reject non-supported tokens (not
possible with ERC20)
• Energy savings. The transfer of ERC223 tokens to a contract is a one step process rather than 2
step process (for ERC20), and this means 2 times less gas and no extra blockchain bloating.
35. ERC223 TOKEN INTERFACE
contract ERC223 {
uint public totalSupply;
function balanceOf(address who) public view returns
(uint);
function name() public view returns (string _name);
function symbol() public view returns (string _symbol);
function decimals() public view returns (uint8 _decimals);
function totalSupply() public view returns (uint256
_supply);
function transfer(address to, uint value) public returns
(bool ok);
function transfer(address to, uint value, bytes data) public
returns (bool ok);
function transfer(address to, uint value, bytes data, string
custom_fallback) public returns (bool ok);
event Transfer(address indexed from, address indexed to,
uint value, bytes indexed data);
36. ERC721
People love collecting
Allow smart contracts to operate as tradable tokens
Each ERC721 is unique (non-fungible)
Support “ownership” functions
Each token is referenced by unique id
Tokens can have metadata (attributes)
37. ERC721
contract ERC721 {
event Transfer(address indexed _from, address
indexed _to, uint256 _tokenId);
event Approval(address indexed _owner, address
indexed _approved, uint256 _tokenId);
function balanceOf(address _owner) public view
returns (uint256 _balance);
function ownerOf(uint256 _tokenId) public view
returns (address _owner);
function transfer(address _to, uint256 _tokenId)
public;
function approve(address _to, uint256 _tokenId)
public;
38. STAY IN TOUCH
Gene Leybzon https://www.linkedin.com/in/leybzon/
https://www.meetup.com/members/90744
20/
https://www.leybzon.com