Friday, June 25, 2021

Data Scraping

What is data scraping?

Data scraping, in its most general form, refers to a technique in which a computer program extracts data from output generated from another program. Data scraping is commonly manifest in web scraping, the process of using an application to extract valuable information from a website.





https://www.cloudflare.com/en-in/learning/bots/what-is-data-scraping/


How Data Scraping Is Done 

 Web scraping is a fairly direct process when viewed at a high level. Code is utilized to pull information, generally via a scraper bot. The bot sends a request to the website, parses the HTML document and converts it into a different format.

Over time, the game has grown more sophisticated. As scraper bots become successful, content protection strategies are beefed up to thwart their efforts. In turn, the bots respond by developing tactics to outmaneuver these new protection mechanisms — and so it goes.   

For the scrapers, content may be derived at little or no expense. Instead of having to write their own content, conduct research and obtain customer reviews, for example, the scrapers may post material on their sites. They avoid having to pay for certain reports and other documents.  


Two Types of Data Scraping

Web Scraping

If you’ve ever copy and pasted information from a website, you’ve performed the same function as any web scraper, only on a microscopic, manual scale.

Web scraping, also known as web data extraction, is the process of retrieving or “scraping” data from a website. Unlike the mundane, mind-numbing process of manually extracting data, web scraping uses intelligent automation to retrieve hundreds, millions, or even billions of data points from the internet’s seemingly endless frontier.

Screen Scraping

Screen scraping is the act of copying information that shows on a digital display so it can be used for another purpose. Visual data can be collected as raw text from on-screen elements such as a text or images that appear on the desktop, in an application or on a website. Screen scraping can be performed automatically with a scraping program or manually with an individual extracting data.


How is web scraping stopped completely?

The only way to totally stop web scraping is to avoid putting content on a website entirely. However, using an advanced bot management solution can help websites eliminate access for scraper bots almost completely.

What is the difference between data scraping and data crawling?

Crawling refers to the process large search engines like Google undertake when they send their robot crawlers, such as Googlebot, out into the network to index Internet content. Scraping, on the other hand, is typically structured specifically to extract data from a particular website.



Sources / References:

https://www.datamation.com/big-data/data-scraping/
https://www.cloudflare.com/en-in/learning/bots/what-is-data-scraping/

Wednesday, June 23, 2021

Cryptocurrency

 Abstract on Cryptocurrency:

Cryptocurrencies have emerged as important financial software systems. They rely on a secure distributed ledger data structure; mining is an integral part of such systems. Mining adds records of past transactions to the distributed ledger known as Blockchain, allowing users to reach secure, robust consensus for each transaction. Mining also introduces wealth in the form of new units of currency. 

Cryptocurrencies lack a central authority to mediate transactions because they were designed as peer-to-peer systems. They rely on miners to validate transactions. Cryptocurrencies require strong, secure mining algorithms. In this paper we survey and compare and contrast current mining techniques as used by major Cryptocurrencies.

 We evaluate the strengths, weaknesses, and possible threats to each mining strategy. Overall, a perspective on how Cryptocurrencies mine, where they have comparable performance and assurance, and where they have unique threats and strengths are outlined.

Facebook Digital Currency - Diem (Libra)

Facebook Digital Currency - Diem ( known as Libra). Offering single-currency stablecoins in addition to the multi-currency coin


Facebook Digital Currency - Diem (Libra) logo

The Diem Association’s mission is to enable a simple global payment system and financial infrastructure that empowers billions of people. The Association’s first step toward creating a more inclusive and innovative financial system began in June 2019 with the announcement of the project. Our goal was to establish a collaborative dialogue early in the journey.

 We have worked with regulators, central bankers, elected officials, and various stakeholders around the world to determine the best way to marry blockchain technology with accepted regulatory frameworks. Our objective is for the Libra payment system to integrate smoothly with local monetary and macroprudential policies and complement existing currencies by enabling new functionality, drastically reducing costs, and fostering financial inclusion.

Blockchains have a number of unique properties that can potentially address some of the problems of accessibility and trustworthiness. These include distributed governance, which ensures that no single entity controls the network; open access, which allows anybody with an internet connection to participate; and security through cryptography, which protects the integrity of funds. 

But existing blockchain systems have yet to reach mainstream adoption. Mass-market usage of existing blockchain-based currencies has been hindered by their volatility and lack of scalability, which have, so far, made them poor mediums of exchange.

What Is Diem?

Diem is a stablecoin similar to Tether (USDT) and other price-pegged cryptocurrencies. It runs on the Diem project’s own Diem blockchain, and the coin is held in a wallet, called Novi.

Naturally, Diem will be used for payments. However, the Diem blockchain will also be programmable, much like Ethereum, so that developers can create custom apps. Diem uses a custom smart contract language called Move that uses a logical constraint called “static typing” to guarantee its security.

The Diem blockchain is powered by validator nodes, which are run by members of the Diem Association. These nodes confirm transactions and validate blocks. This diagram outlines the process:


Image Source: https://cryptobriefing.com/diem-introduction-facebooks-stablecoin/

Efficiency is an important part of the Diem blockchain. Diem’s testnet has been criticized for handling between 6 and 24 transactions per second, far less than non-blockchain payment networks like Visa and Mastercard. But in practice, Diem’s blockchain may be faster, as it aims to support 1000 transactions per second.

On top of this, Diem is promising near-zero transaction fees. On Diem, interest is paid to validators that comes from reserve assets. That means Diem does not need to take a 1%-3% cut of each transaction to make money, as payment companies currently do.

History of Diem

Diem has been under development for nearly two years in various forms. These are the most important milestones in its history.

Early History

In May 2018, Facebook messaging Vice President David Marcus was appointed to a new blockchain division within the company. Marcus previously was president of PayPal and a director on the board of Coinbase. These facts led many commentators to predict that Facebook was planning a crypto-based payments platform.

Further clues emerged as Facebook hired more crypto developers, who eventually leaked details to the press. The Wall Street Journal was one of the first to report on the company’s plans.

At that time, Facebook’s crypto product was supposedly intended for use via WhatsApp in India as a remittances tool. That plan has apparently been abandoned in favor of broader goals.

Official Announcement

In June 2019, the Facebook-backed Libra Association officially announced Libra and revealed the structure of the project in detail.

The Libra Association announced that the blockchain would be powered by a consortium of 27 major companies operating independently of Facebook. Meanwhile, Facebook would profit from those plans by building the Calibra wallet for the cryptocurrency (now called Novi) and by having a single governance vote.

Though the Association remains active, not all of its original members remain involved. By the end of 2019, several members of the Libra Association left the project, including Visa, Mastercard, PayPal, eBay, and Stripe, as well as Mercado Pago and Booking Holdings. That forced the project to rebuild its Libra Association with the remaining members and new additions.

The project also faced numerous regulatory roadblocks at the time of its announcement, including pushback from the U.S. Senate and several European regulators. Libra’s 2020 launch date came and went, and the project remained mostly silent throughout 2020.

The Diem Rebrand

In December 2020, Libra returned with a new name, Diem, and announced plans to go live in early 2021.

What’s the Difference Between Diem and Bitcoin?

If you were introduced to cryptocurrencies through Bitcoin like most people, then forget everything you know. The Diem Dollar is very different from Bitcoin, both in the way that it works and the way it’s controlled. 

For starters, the Diem Dollar is a stable coin built on a permissioned blockchain network. Unlike Bitcoin, it’s not designed as an open network which anyone can participate in. Another difference is that Diem is directly connected to the US Dollar. This distinguishes it from Bitcoin, which isn’t connected to any specific stable asset making its value volatile and unstable. This means that a Bitcoin’s value changes a lot more unpredictably, whereas Diem’s value won’t fluctuate any more or less than the price of a US Dollar.

Another crucial difference between the two is that Diem is a centralized currency. It’s centralized by the Diem Association which oversees its development and the ways in which it can be used. That’s worlds apart from Bitcoin, a decentralized cryptocurrency that isn’t overseen by any one person, group or company. 

Finally, since the Diem Dollar is pegged to a fiat currency, it isn’t connected to any finite resource. The US Dollar is a currency whose value is in direct correlation to the number of Dollars in circulation and is no longer connected to the amount of gold that the US owns. This makes the number of Dollars that can be printed virtually unlimited. By contrast, the number of Bitcoin in circulation is very much finite, with a cap of 21 million in existence.

By introducing Diem, Facebook and the Diem Association are changing the way we imagine cryptocurrencies. Unlike Bitcoin, Diem isn't introducing a new method of digital payment. It’s simply a new way of exchanging money digitally. This should make it a lot easier for non-tech savvy individuals to start using cryptocurrencies to make digital payments for everyday things like groceries and taxi rides.

Conclusion 

Cryptocurrencies have been around for a long time, but the Diem Association could be the group that makes them available to billions globally. By creating a stable coin backed by the US Dollar, the Diem Association has created a new type of cryptocurrency –– one that’s accessible, easy to understand, and easy to use in everyday life. Combine that with Uber, PayU, and Shopify’s user base, and Diem is well on its way to becoming the dominant cryptocurrency over the next few years.

Sources / References Content From:


https://cryptobriefing.com/diem-introduction-facebooks-stablecoin/

https://www.diem.com/en-us/white-paper/

https://www.theguardian.com/technology/2019/jun/18/what-is-libra-facebook-new-cryptocurrency

https://en.wikipedia.org/wiki/Diem_(digital_currency)

https://www.firstdag.com/blog/why-diem-is-better-than-bitcoin/

Quantum machine learning

 Quantum machine learning Abstract:

Quantum Machine Learning bridges the gap between abstract developments in quantum computing and the applied research on machine learning. Paring down the complexity of the disciplines involved, it focuses on providing a synthesis that explains the most important machine learning algorithms in a quantum framework. Theoretical advances in quantum computing are hard to follow for computer scientists, and sometimes even for researchers involved in the field. 

The lack of a step-by-step guide hampers the broader understanding of this emergent interdisciplinary body of research. Quantum Machine Learning sets the scene for a deeper understanding of the subject for readers of different backgrounds.

The author has carefully constructed a clear comparison of classical learning algorithms and their quantum counterparts, thus making differences in computational complexity and learning performance apparent. This book synthesizes of a broad array of research into a manageable and concise presentation, with practical examples and applications. 
 


What is Quantum Machine Learning?

Quantum machine learning is a research area that explores the interplay of ideas from quantum computing and machine learning.

For example, we might want to find out whether quantum computers can speed up the time it takes to train or evaluate a machine learning model. On the other hand, we can leverage techniques from machine learning to help us uncover quantum error-correcting codes, estimate the properties of quantum systems, or develop new quantum algorithms.

Quantum machine learning (QML) is built on two concepts: quantum data and hybrid quantum-classical models.

Why Quantum Machine Learning?

In 2017, Microsoft CEO Satya Nadella explained the difference in computing power and method of classic and quantum computers using an example of a corn maze. The modern-day classical computers would use the brute force and backtracking algorithm to find a path through the maze.

It would choose a path, hit an obstruction, backtrack to the original starting point, choose another path and continue until it finds a way out. It will surely find a solution but at the cost of a lot of time. Imagine your mobile is draining its battery and the algorithm is running for long with no final solution.

This is where quantum computers come to rescue. They unlock amazing parallelism and traverse every path in the corn maze simultaneously to find you an optimal solution in very less time and an exponentially reduced number of steps. It’s like sending a ‘n’ number of drones to the ‘n’ number of paths and get all the results, i.e. path information in unit time.

Where Can We Apply Quantum Machine Learning?

  • Model classical data on quantum computers, or create novel quantum- inspired classical algorithms for faster computation and better results.
  • As the feature space of the problem domain expands, the computations become really expensive for classical computers. Using superposition and other quantum properties, quantum machine learning helps extensively in kernel evaluation and optimization.
  • Quantum machine learning also has the capability of mapping the trillions of neurons in our brain and decoding the genetic makeup.
  • Supervised learning and adaptive layer-wise learning with the help of quantum classifiers and neural networks
More seminar topics related to Quantum Machine Learning:

Quantum Cryptography
Quantum Internet
Quantum Processing Units
Quantum Supremacy
Quantum Network
Quantum Logic Gate
Quantum neural networks


Sources / References:

https://www.researchgate.net/publication/264825604_Quantum_Machine_Learning_What_Quantum_Computing_Means_to_Data_Mining

https://pennylane.ai/qml/whatisqml.html

https://www.geeksforgeeks.org/working-of-quantum-machine-learning/

https://en.wikipedia.org/wiki/Quantum_machine_learning