投稿時間:2022-02-13 12:08:40 RSSフィード2022-02-13 12:00 分まとめ(9件)

カテゴリー等	サイト名等	記事タイトル・トレンドワード等	リンクURL	頻出ワード・要約等/検索ボリューム	登録日
TECH	Techable（テッカブル）	リスニング力強化へ。アルクの英語学習アプリ「booco」にディクテーション機能追加	https://techable.jp/archives/173173	booco	2022-02-13 02:00:49
python	Pythonタグが付けられた新着投稿 - Qiita	awswranglerにて pyarrow.lib.ArrowTypeError: Did not pass numpy.dtype object のエラー	https://qiita.com/Hisaaki-Kato/items/ef40d01fd99caecd9282	awswranglerにてpyarrowlibArrowTypeErrorDidnotpassnumpydtypeobjectのエラー最近、業務でデータ基盤の構築をしており、その中でETL処置のためにawswranglerというライブラリを使用することがあります。	2022-02-13 11:46:47
python	Pythonタグが付けられた新着投稿 - Qiita	"How to GraphQL" チュートリアルからのメモ	https://qiita.com/Buffalo46/items/a8e9df6097a758d4d1f6	誰のためにもならない記事になってしまったけれど、これを描きながらチュートリアルを進めることで、曖昧な理解にとどめなかった箇所がいくつかあるので個人的にはとても満足。	2022-02-13 11:30:50
AWS	AWSタグが付けられた新着投稿 - Qiita	awswranglerにて pyarrow.lib.ArrowTypeError: Did not pass numpy.dtype object のエラー	https://qiita.com/Hisaaki-Kato/items/ef40d01fd99caecd9282	awswranglerにてpyarrowlibArrowTypeErrorDidnotpassnumpydtypeobjectのエラー最近、業務でデータ基盤の構築をしており、その中でETL処置のためにawswranglerというライブラリを使用することがあります。	2022-02-13 11:46:47
海外TECH	Ars Technica	Astronomers now say the rocket about to strike the Moon is not a Falcon 9	https://arstechnica.com/?p=1833819	chinese	2022-02-13 02:10:48
海外TECH	DEV Community	On Blockchain — Understanding the absolute basics.	https://dev.to/ceonyema/on-blockchain-understanding-the-absolute-basics-oog	On Blockchain ーUnderstanding the absolute basics In this post we are going to learn about blockchain in its simplest form my objective for this post is that by the end you would have a better understanding of the blockchain and also be able to explain to your friends or that year old kid I m going to start with an introduction then we define blockchain and clarify some of our misconceptions after which we would talk about the types and quickly see some applications Alright let s dive right in Before we begin to learn what blockchain is first I would like to start with what the blockchain is not Contrary to what some people think or assume blockchain is not a cryptocurrency it is not the bitcoin it is not limited to financial transactions the blockchain is much more than that as it s not for solving just one issue for some people but can fix many problems for everyone It s the foundation on which these other structures are built upon It s so much more that we keep on finding more and more ideas where this technology can help solve problems every day Hopefully by the end of this piece you would get to understand this revolutionary technology For simplicity I would limit my examples to the use of financial transactions So What is blockchain First what are blocks Let s say I m to record all my financial transactions and present them as a single big database encyclopedia I would record on a single sheet of a paper list of transactions on grocery including amounts date grocery store etc until it gets filled up I would run a validation exercise cross checking my bank statements and asking of my friends I went with to the grocery store that day to help me check if the values are accurate On successful validation I would save this sheet of paper inside the encyclopedia where I can t remove it until the day I m going to submit it Then I would get a new sheet of paper on which I would continue to record subsequent transactions The database encyclopedia can be likened to represent the blockchain while the sheet s of paper the block s However in reality the blockchain operates a little differently It abides by certain ideologies which make it unique from our traditional database record keeping system This is then going to lead us into understanding some of the principles guiding the blockchain The blockchain core principles DecentralizationThis principle is all about delegating power decision making ability supervision maintenance control from a central entity a person group authority or an administrator to a dispersed network of nodes all the nodes on the network contain the same information and have equal rights It ensures no entity can claim ownership or control of the blockchain Decentralized databaseA decentralized database is one where there is no centralized storage of data or system administrator hence no single source of failure or weakness in a system And that is essentially what the blockchain is all about Distributed peer to peer networkPp short for peer to peer is a model based on a simple decentralization principle instead of relying on a centralized administrator or server to control communication functions the blockchain rather utilizes a decentralized network communication model between two nodes peers which aids storing and sharing of records without the need for a central intermediary Unlike traditional client server systems where there is a dedicated central server where a client downloads from and a server to store the pp system is maintained by a network of nodes ーwhere each node can act both as server and a client server when another client is making a request and a client when it is making its request SecurityAll records are individually encrypted The blockchain is built in such a way that together with all other underlying principles security is prioritized such that taking part in the network is far more economically incentivized than attacking it Also because of its decentralized nature and no single central point of control it s nearly impossible for hackers to attack or attempt to hack into it if anyone were to alter a single copy of the block it would no longer contain the same copy of information distributed across other nodes hence would not be recorded into the block ImmutabilityRemember when I said the blockchain operates a little differently from how our database functions here is another unique difference There are what are known to be CRUD Create Read Update Delete functions performed on persistent storage applications Ability to create a record read a record update a record and finally delete a record On the blockchain the last two operations were omitted You can only be able to create and read a record without updating or deleting it This is how the blockchain got its immutability property the ability of records to remain unchanged or almost impossible to reverse a recorded transaction Group consensusBefore data can be recorded on the blockchain in permanence all the data that are being independently recorded by the participating nodes computers are periodically checked and if or more than of those nodes agree upon the validity of a record it gets committed to the blockchain never to be altered again This ensures that whatever data we read of the blockchain comes with the backup that was recorded by the majority of the participating nodes So essentially a consensus mechanism allows many participants to maintain one truth together which roughly translates to we are participants therefore we can all check it and whatever majority of us decides is the truth because the majority of us cannot independently record false data Having established the basics and core principles of the blockchain we can now agree on a higher level overview that theBlockchain is a decentralized database distributed across participating peer to peer nodes which is immutable and very secure Now we have understood what blockchain is Let s go back to clarify one of our earlier misconceptions about the relationship between blockchain and cryptocurrencies Blockchain and CryptocurrenciesMost people got exposure to the blockchain through the knowledge of a cryptocurrency of which bitcoin is an example and the first to be created in so it s not unusual for misconceptions to exist But here is the real deal cryptocurrencies are digital decentralized disintermediated trustless currencies that get transacted through the blockchain In essence because of the infrastructures and principles by which the blockchain operates cryptocurrencies can run on them to make it possible for secure peer to peer transactions to happen between people without any third party whilst ensuring privacy and accurate record of transactions To say that the blockchain is equal to bitcoin or any other cryptocurrency is like saying that a railroad is equal to a train they are not rather the train can transport people because it can travel on top of the railroad Types of blockchainOftentimes when we hear of the blockchain we generally think we have just one type of blockchain on which every other thing is built upon Although all blockchains operate on certain common principles They can also be built in a variety of different ways to best offer solutions to a specific use case or application Fundamentally we have just two types of blockchain the public and private blockchain but as we are going to see shortly we have four of them in total Public blockchainIn a public blockchain anyone anywhere in the world can become part of the blockchain network read the data send and receive data and upon validation would be added to the ledger They would be able to join the consensus process hence they are often referred to as permission less because they are non restrictive By nature this type of blockchain is open source and completely decentralized Examples are the Bitcoin and Ethereum blockchain Private blockchainThey are blockchains controlled by a single entity often referred to as a permissioned blockchain because the central admin decides and permits who becomes a part of the blockchain As a result there is a partial level of decentralization security and they are more likely to encounter fraud or error whilst enjoying a faster and shorter time validating data as a result of few participating nodes high level of privacy and a higher level of scalability This type of blockchain is usually used within a single organization where only the selected members are allowed to be part of the blockchain Consortium blockchainThe consortium blockchain is a semi decentralized type of blockchain unlike the private blockchain more than one entity manages the blockchain as a result there is a higher level of decentralization security than the private blockchain In this type of blockchain they can consist of a group of large financial firms here each selected participating firm would manage a node on the consortium blockchain Hybrid BlockchainA hybrid type of blockchain is that type that can combine the best of both public and private types of blockchain examples are the Dragonchain and Xinfins hybrid blockchain However there are some advantages and disadvantages attached to each type of blockchain so it s always best when we define what we want set priorities and then choose what type of blockchain to implement that would offer the best solution to our problems Applications of the blockchainThere is no use for medical knowledge if it can t be applied to solving an abnormality in the body You might have that same question for the use of blockchain well we are going to quickly go through a few of them The use of blockchain can help us ensureTransparent voting system Insurance through a smart contract Effective cloud storageRecord management Curbing money launderingFinancial management and accounting Securely share medical information Data protection and storageEffective Identity management Borderless transfer of money across countries easilyProper Asset tracking across the supply chain Thank you	2022-02-13 02:26:58
金融	ニュース - 保険市場TIMES	「フリーペットほけんミニ（MOFFME限定プラン）」販売開始	https://www.hokende.com/news/blog/entry/2022/02/13/120000	「フリーペットほけんミニMOFFME限定プラン」販売開始MOFFME限定で申し込みが可能ペット保険の比較相談サービス「MOFFMEモフミー」を運営する株式会社Wizleapは年月日、犬と猫のペット保険を扱う株式会社FPCと提携し、「フリーペットほけんミニMOFFME限定プラン」の販売を開始することを発表した。	2022-02-13 12:00:00
北海道	北海道新聞	貨物列車と衝突、軽トラの男性死亡　恵庭の踏切、列車一時運休	https://www.hokkaido-np.co.jp/article/645133/	恵庭市島松寿町	2022-02-13 11:13:37
北海道	北海道新聞	最年少五冠の藤井「喜びを実感」　王将奪取から一夜明け会見	https://www.hokkaido-np.co.jp/article/645129/	藤井聡太	2022-02-13 11:06:00