Blockchain EOS
the content of this article comes from: financial code of the people's Republic of China: application edition, China Law Press
EOS can be understood as enterprise operation system, which is a blockchain operating system designed for commercial distributed applications. EOS is a new blockchain architecture, which aims to extend the performance of distributed applications
blockchain originated from bitcoin. On November 1, 2008, a person who called himself Satoshi Nakamoto published the article "bitcoin: a peer-to-peer e-cash system", which elaborated the architecture concept of e-cash system based on P2P network technology, encryption technology, timestamp technology, blockchain technology, etc., marking the birth of bitcoin
extended data
the main features of EOS are as follows:
1, decentralization. Blockchain technology does not rely on additional third-party management institutions or hardware facilities, and there is no central control. In addition to the self-contained blockchain itself, each node realizes information self verification, transmission and management through distributed accounting and storage. Decentralization is the most prominent and essential feature of blockchain
2. Openness. Blockchain technology is based on open source. In addition to the private information of all parties involved in the transaction is encrypted, the data of blockchain is open to everyone. Anyone can query blockchain data and develop related applications through the open interface, so the information of the whole system is highly transparent
3. Independence. Based on consensus specifications and Protocols (similar to various mathematical algorithms such as hash algorithm used by bitcoin), the whole blockchain system does not rely on other third parties, and all nodes can automatically and safely verify and exchange data in the system without any human intervention
source: Network - EOS
EOS: EOS can be understood as enterprise operation system, which is a blockchain operating system designed for commercial distributed applications. EOS is a new blockchain architecture introced by EOS software, which aims to realize the performance expansion of distributed applications. Note that it is not a currency like bitcoin and Ethereum, but a token based on the EOS software project, known as blockchain 3.0
The main features of
EOS are as follows:
1. EOS is a bit similar to Microsoft's windows platform. By creating a developer friendly underlying platform of blockchain, it supports multiple applications to run at the same time and provides the underlying template for the development of DAPP
EOS solves the problems of delay and data throughput by means of parallel chain and dpos. EOS can process thousands of data per second, while bitcoin has about 7 transactions per second, and Ethereum has 30-40 transactions per second There is no service charge for EOS, and the general audience is more extensive. The network and computing resources needed to develop DAPP on EOS are allocated according to the proportion of EOS owned by developers. When you have EOS, it is equivalent to having computer resources. With the development of DAPP, you can lease your EOS to others. From this point alone, EOS has a wide range of value. To put it simply, if you have an EOS, it is equivalent to having a set of rent to collect rent for others, or having a piece of land to rent for others to build a house. digital currency exchange "currency exchange"
development prospects
through a more in-depth understanding of EOS, EOS is quite valuable for investment. First of all, as the first to launch smart contracts, ETH runs smart contracts on eth, which is not free and depends on your gas. If gas runs out, the contract will stop. According to people who have used eth trading platform, it runs slowly and is very expensive, However, there is no such problem in EOS. The operation contract on EOS depends on the number of EOS you have. The more EOS you have, the more you can rent. With the continuous development, the more expensive the price will be; Secondly, it's very simple to develop DAPP on EOS, and you don't need to write many moles, because EOS itself builds the bottom mole for developers, which provides a platform and greatly reces the threshold of development; Thirdly, as an ordinary investor, owning EOS is equivalent to owning real estate, which can be used to rent and earn money. With the development of DAPP, the number of users increases, and the price increases irresistibly
EOS is a public chain system at the bottom of blockchain developed by block. One, which is specially designed to support decentralized application of Commerce, and its code is open source
bitcoin is called blockchain 1.0 because it opens up the world of digital cryptocurrency and takes a decisive step from 0 to 1
Ethereum is known as blockchain 2.0, because it provides Turing complete virtual machine that can run smart contracts, bringing unlimited possibilities
and EOS is called blockchain 3.0, why? Two words: performance
The positioning of EOS is the slogan of its home page:English: the most powerful infrastructure for decentralized applications
Chinese: the most powerful decentralized application infrastructure
EOS expects to be an enhanced version of Ethereum, a high-throughput intelligent contract platform
although Ethereum has complete functions, it is limited by its design choice. Due to the block output speed of 15 seconds, the transaction throughput is far from large-scale practical level, which is only about 30 ~ 40tps (transaction / s). EOS, on the other hand, has chosen a different technology route, with the goal of achieving a considerable million TPS, which is quite attractive considering visa's actual processing speed of 1700tps
consensus mechanism of EOS
the reason why the throughput of bitcoin and Ethereum is so low is that they are constrained by the application scenario they envision and the consensus mechanism they choose for the scenario - both of them assume that the environment in which the system runs is totally untrustworthy, so they both adopt the consensus mechanism of proof of work
consensus, as the name suggests, is to reach a unified understanding of something - for blockchain, something refers to the confirmation of the transaction - any node to submit a transaction needs everyone's approval
the pow mechanism currently adopted by bitcoin and Ethereum is the design of the legendary Nakamoto Tsung. Under this mechanism, in order to obtain the bookkeeping right and digital currency reward, miners need to constantly dig for the compliant hash value, and confirm and package the transaction data through the consensus of hash value. POW has no access threshold, and any node has equal rights to participate in bookkeeping. Of course, the probability of winning is related to computing power:
the price of ram is based on Bancor algorithm, that is, it is regulated by market supply and demand: if the supply of ram exceeds the demand, more EOS certificates are needed to buy ram, At this time, more EOS certificates can be obtained by selling ram
memory is a consuming resource, which cannot be redeemed and can only be bought and sold. Take the issue of currency on EOS as an example. At present, the issue of currency requires 20m of memory. An EOS can buy 20KB. According to the current storage price, issuing a currency will consume 1000 EOS. This is the source of EOS memory consumption
Course Overview
this course is for friends who are interested in the development of EOS decentralized application. The course covers the core concepts of EOS DAPP development, the development and deployment of smart contracts, and how the front page interacts with EOS blockchain. Finally, a complete DAPP development based on react and EOS is completed
Chapter 1: enter the world of EOS
to understand the core concepts of EOS, such as positioning and characteristics, consensus mechanism, payment computing model, etc
Chapter 2: Hi EOS
understand the overall framework of EOS node software and the functions of node server, wallet server and command-line tools, learn how to configure and start EOS node server and wallet server, and preliminarily understand the use of command-line tools
Chapter 3: wallet, key and account
understand the three core concepts related to personal identity in EOS: wallet, key and account, and learn how to use command-line tools to create wallet, key and account
Chapter 4: development and interaction of smart contracts
understand the concept and function of smart contracts, learn how to write and compile EOS smart contracts, and learn how to deploy and interact with contracts using command-line tools
understand the persistence mechanism of state in EOS smart contract, and learn to use multi index table to save contract state
Chapter 5: issue your own tokens
learn the principle and implementation mechanism of issuing tokens on EOS, and master how to use command-line tools to issue, transfer and view the balance of tokens through practical operation
Chapter 6: use code to interact with smart contract
understand the principle of interaction between application and EOS blockchain, and learn to use JSON RPC interface and eosjs encapsulation library to access EOS blockchain
Chapter 7: DAPP development of practical notes
comprehensively use EOS knowledge, use react to complete a decentralized application of EOS notes, and learn the complete process from requirement analysis to code implementation
The above course address is as follows: EOS tutorialHand in hand to teach you to buy your life's first EOS! I hope it's useful. I've adopted it. I've put in some myself< br />
EOS% refers to the percentage of eosinophils in the total number of white blood cells, the normal value is 0.5% - 3%< 1. Eosinophilia:
(1). Allergic diseases: bronchial asthma, drug allergy, urticaria, food allergy, angioneurotic edema, serum diseases and other peripheral blood eosinophilia can reach more than 10%
(2). Parasitic diseases: schistosomiasis, Ascaris lumbricoides The number of eosinophils in blood, such as hookworm disease, is usually 10% or more. The number of eosinophils increased significantly in some patients with parasitic infection, resulting in the total number of white blood cells reaching tens of thousands, more than 90% of which were eosinophilic leukemoid reaction
(3) skin diseases such as eczema, exfoliative dermatitis, pemphigus, etc The eosinophils in peripheral blood of patients with psoriasis were slightly or moderately increased
(4). Hematological diseases such as chronic myeloid leukemia, eosinophilic leukemia, lymphoma, multiple myeloma, eosinophilic granuloma, etc. the eosinophils in peripheral blood were increased in different degrees, Some malignant tumors: some epithelial tumors such as lung cancer can cause eosinophilia
(6). Some infectious diseases: most eosinophils decrease in acute infectious diseases, but increase in eosinophils in scarlet fever
(7) Hypopituitarism, allergic interstitial nephritis and so on are often accompanied by eosinophilia
2. EOSINOPENIA:
it is common in the early stage of typhoid fever, paratyphoid fever, major surgery, burn and other stress states, or after long-term application of adrenocortical hormone, and its clinical significance is very small
please take it if you are satisfied
wish you good health