CoreNET Solutions

office@corenet.co.rs
Miloja Pavlovića 9 office 9A
34000 Kragujevac, Serbia
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Use services (start -> run -> services.msc) and look for the postgresql-[version] service.

 

select table_name, column_name from information_schema.columns where column_name like ‘%column_name%’;

Abu Abdulah Muhamed ibn Musa el Horezmi (pers. عَبْدَالله مُحَمَّد بِن مُوسَى اَلْخْوَارِزْمِي‎; oko 783. Hiva, Horezm,— oko 850. Bagdad) je bio persijski matematičar, astronom, astrolog i geograf iz IX veka. Horezm, gde je on rođen, je današnja Hiva, dok se Horezmija, zemlja na donjem toku reke Amu-Darja (stari Oksus) nalazi na području današnjeg Uzbekistana.

Horezmi je u doba vladavine kalifa Mamuna vodio državnu biblioteku i bio jedan od aktivnih članova Kuće mudotosti.

El Horezmi je uveo modernu numeričku notaciju. Malo se zna o El Horezmijevom životu; bio je član bagdadske Akademije nauka i pisao o matematici, astronomiji i geografiji.

Horezmi je takođe uspeo da objasni staru indijsku baštinu i starogrčke naučne rezultate iz oblasti matematike.

U toku osovnog obrazovanja detaljno je upoznao glavne smernice iranske predislamske matematike i astronomije. Kako je nastavio svoja istraživanja na tom polju, prerastao je u jednog od najlavnijih predstavnika univerziteta u Džundišapuru.

Dok je radio na određenim naučnim projektima u sklopu velikog univerziteta u Džundišapuru, detaljno je upoznao staroindijsku i staropersijsku astronomsku tradiciju i naučnu literaturu. Kasnije se pokazalo da su ta istraživanja bila od velikog značaja zato što je on mnogo jednostavnije i preciznije uspeo da neke indijske i pahlavidske knjige prevede na arapski jezik. Ipak, ne treba zaboraviti da njegova slava nije retultat njegovih prevoda.

Mnogi ga smatraju ocem algebre. Osim toga, izraz algoritam, kojim se prvobitno opisivao način računanja decimalnim brojevima, a formulisao ga je Horezmi, preuzet je iz latinske transkripcije njegovog imena.

Matematika[uredi]

Kako tvrdi deo istoričara matematike, muslimani su upoznali staroindijski brojevni sistem posredstvom slavnog dela al-Đam va at-tafrik fi hisab al-Hind [Sabiranje i oduzimanje u indijskoj aritmerici] Muhameda ibn Muse Horezmija. S velikom izvesnošću možemo tvrditi da je ta knjiga najstarije delo koje je u islamskom svetu napisano o aritmetici. Međutim, iako njen arapski originalni primerak još uvek nije pronađen, dostupni su nam njeni prevodi na latinski jezik. Horezmi je u toj knjizi sjajno razjasnio staroindijsku brojevnu osnovu i preneo je u islamski svet.

Horezmijeva slava ponajviše potiče od njegovog eminentnog remek-dela al-Đabr [Algebra] zbog kog ova matematička disciplina koju je Horezmi utemeljio dobija upravo taj naziv u kasnijoj literaturi. Ovaj naziv se i danas koristi na Zapadu da bi se ukazalo na ovu matematičku disciplinu. Dakle, naziv ove nauke, koji se u savremenom francuskom jeziku upotrebljava u oblku reči algebre, a u engleskom algebra, vuče svoje leksičke korene od arapskog naziva al-đabr, spomenutog u naslovu Horezmijeve čuvene knjige. Međutim, on daje opšti metod (Al Horezmijevo rešenje) za nalaženje dva korena kvadratne jednačine

{\displaystyle ax^{2}+bx+c=0\,} (gde je {\displaystyle {a\neq 0}\,});

on je pokazao da su korenovi

{\displaystyle x_{1}={\frac {-b+{\sqrt {b^{2}-4ac}}}{2a}}}
{\displaystyle x_{2}={\frac {-b-{\sqrt {b^{2}-4ac}}}{2a}}}

U svojoj knjizi Račun sa Hindu brojkama on je opisao indijsku notaciju (kasnije zbog uticaja ove knjige nazvanu „arapskim“ numeralima), u kojoj vrednost numerala zavisi od njihovog položaja, i koja uključuje nulu.

Notacija (koja je u Evropu stigla u latinskom prevodu posle 1240) od ogromne je praktične vrednosti i njeno prihvatanje je jedan od velikih koraka u matematici.

Iz sačuvanih rukopisa vidi se da je deset znakova (1-9 i 0) imalo skoro svoj sadašnji oblik sredinom 14. veka.

Njegovo delo „Knjiga izračunavanja integrala i jednačina“ (arap. الكتاب المختصر في حساب الجبر والمقابلة, al-Kitāb al-muẖtaṣar fī ḥisāb al-ğabr wal-muqābala) predstavlja kompilaciju pravila za rešavanje linearanih kvadratnih jednačina i problema geometrije i srazmera, dato je nešto više od 800 primera, od kojih su neke već ranije bili upotrebili Neovavilonci. To je njegovo glavno delo, ali je, nažalost, u arapskom originalu izgubljeno. U dvanaestom veku preveo ga je na latinski Gerard Kremonski. Ovo Al Horezmijevo delo upotrebljavalo se sve do šesnaestog veka kao glavni matematički udžbenik na evropskim univerzitetima i, zahvaljujući njemu, u Evropi je uvedena algebarska nauka, a zajedno s njom i samo njeno ime.

Prevod ovog dela u XII veku na latinski jezik omogućio je vezu između velikih hinduističkih i arapskih matematičara i evropskih naučnika. Al Horezmijeva knjiga, koja je u Evropi postala poznata pod latinskim nazivom Algoritmi de Numero Indorum, što je trebalo da znači „Al Horezmi, o indijskim brojevima“. Međutim, zaboravilo se da je Algoritmi ime autora i ustalio se prevod „Postupci računanja indijskim brojevima“. Od tada reč algoritam označava proizvoljan, obično matematički postupak i odomaćila se u oblasti računarstva.

U svojim spisima o algebri koja je didaktičko delo, pokušao je da pokaže način na koji je bilo moguće primeniti algebru u svakodnevnom životu tadašnjeg islamskog carstva.

Prema Rošenovom prevodu možemo uočiti da je pokušao da pokaže da: ono što je lako i korisno u aritmetici, moguće je primeniti u raznim svakodnevnim situacijama(pravo, suđenja, trgovina, merenje zemlje, prokop kanala, geometrijskim proračunima…)

Nakon što je predstavio prirodne brojeve, uvodi glavno pitanje u prvom delu svoje knjige – rešenje jednačina. Njegove jednačine su ili linearne ili kvadratne i sastavljene su od jedinica, korena i kvadrata. Za njega je npr, jedna jedinica bila jedan broj, jedan koren je bila nepoznata i kvadrat nepoznata na kvadrat. Iako ćemo u daljim primerima koristiti današnju algebarsku notaciju brojeva kako bi čitalac mogao bolje da razume, trebalo bi istaći da Al Horezmi nije koristio nikakve simbole već samo reči.

Prvo postavlja jednačinu u neki od sledećih oblika:

  1. kvadrati jednaki korenu;
  2. kvadrati jednaki broju;
  3. koreni jednaki broju;
  4. kvadrati i koreni koji su jednaki broju kao npr x² + 10x = 39;
  5. kvadrati i brojevi koji su jednaki korenima kao npr x² + 21 = 10x;
  6. koreni i brojevi jednaki kvadratima kao npr 3x + 4 = x².

Dalje se završava koristeći operacije al-ŷabr i al-muqabala.

Al Horezmijevi geometrijski dokazi unose kontroverznost među naučnike. Pitanje koje ostaje i dalje bez odgovora jeste da li je poznavao Euklidov rad. Treba imati na umu da je u njegovoj mladosti za vreme Rašidove vladavine, prevedeno delo Elementi na arapski i da je prevodilac bio jedan od dva Horezmijeva saradnika u Kući mudrosti. Rašid kaže da je Horezmijevo delo verovatno bilo inspirisano Elementima. Međutim neki tvrde da su mu Elementi bili zapravo potpuno nepoznati. Iako nije zasigurno poznato da li je poznavao Euklidovo učenje moguće tvrditi da je bilo uslovljeno drugim delima o geometriji.

U daljem delu ispituje aritmetičke zakone i kako se oni pojavljuju i koriste među algebarskim objektima. Primer je kako pomnožiti izraze kao (а + bx)(c + dx). Sledeći deo se bazira na korišćenju i primerima. Opisuje pravila za nalaženje površine geometrijskih figura kao što je krug i zapremine tela kao sto su sfera i piramida. Ovaj deo ima mnogo više sličnosti sa hebrejskim i indijskim tekstovima nego sa nekim grčkim delom.

U poslednjem delu knjige se bavi kompleksnim islamskim pravilima nasleđivanja ali koristi malo algebre koju je pokazao ranije, više nalazi rešenja u linearnim jednačinama.

Među kasnijim matematičarima na koje je uticao El Horezmi bili su Omar Hajam, Leonardo Fibonači iz Pize (posle 1240.) i magister Jakob iz Firence, čija italijanska rasprava o matematici iz 1307. god, sadrži, kao i Leonardova dela, pet tipova kvadratnih jednačina, koje su se nalazile u delima muslimanskih matematičara. Al Kajamova algebra [3], koja označava značajan napredak od Al Horezmijeve algebre, sadrži geometrijska i algebarska rešenja jednačina drugog stepena i jednu izvrsnu podelu jednačina.

Preuzeto sa wikipedia.org

Zdravo, Beograde! Cloudflare network spans 30 European cities

Since Cloudflare began with our very first data center in Chicago, we are especially excited that our expansion takes us to its sister city. Where the Sava meets the Danube, Belgrade (Serbia) is home to Cloudflare’s 107th data center.

As a member of the Serbian Open Exchange, the leading internet exchange point in the country, we are excited to help make 6 million websites even faster for nearly 6 million Internet users. Belgrade is seeing growth in employment across the technology industry, ranging from the Microsoft Development Center to Serbian gaming company Nordeus to startups such as TeleSkin and Content Insights.

The addition of Belgrade brings Cloudflare’s growing European network to 30 cities, joining existing facilities in Amsterdam, Athens, Barcelona, Berlin, Brussels, Bucharest, Copenhagen, Dublin, Dusseldorf, Hamburg, Helsinki, Frankfurt, Kiev, Lisbon, London, Madrid, Manchester, Marseille, Milan, Moscow, Oslo, Paris, Prague, Rome, Sofia, Stockholm, Vienna, Warsaw, and Zurich.

Text taken from https://blog.cloudflare.com/belgrade-107th-datacenter/

CDN is short for content delivery network.

A content delivery network (CDN) is a system of distributed servers (network) that deliver webpages and other Web content to a user based on the geographic locations of the user, the origin of the webpage and a content delivery server.

This service is effective in speeding the delivery of content of websites with high traffic and websites that have global reach. The closer the CDN server is to the user geographically, the faster the content will be delivered to the user. CDNs also provide protection from large surges in traffic.

Servers nearest to the website visitor respond to the request. The CDN copies the pages of a website to a network of servers that are dispersed at geographically different locations, caching the contents of the page. When a user requests a webpage that is part of a content delivery network, the CDN will redirect the request from the originating site’s server to a server in the CDN that is closest to the user and deliver the cached content. The CDN will also communicate with the originating server to deliver any content that has not been previously cached.

The process of bouncing through a CDN is nearly transparent to the user. The only way a user would know if a CDN has been accessed is if the delivered URL is different than the URL that has been requested.

Content delivery networks are used for B2B interactions and in serving content to consumers. Today, as more aspects of daily life move online, organizations use content delivery network to accelerate static content, dynamic content, mobile content, ecommerce transactions, video, voice, games and so on.

CDN Advantages

But what happens if I want to run traffic from Argentina? or South Africa? or Australia and India?

The visitor clicks the banner when he’s in India, then he’s routed through the DNS to my landing page hosted in the USA and then he clicks the button to the offer and goes back to another server hosted who knows where.

The response time could be enough for the impatient user to close their browser and surf somewhere else. But I’, still being charged for that click.

Originally the CDNs were being used to host heavy things like images, CSS, scripts and more, but because many times affiliates use simple landing pages (especially for mobile traffic) you can host the whole landing page in the CDN as long as it doesn’t use PHP.

Also, because the content is distributed in several servers it means the traffic is balanced instead of saturating just one server that could go down anytime while I’m sleeping and there goes a few hundreds or thousands from my wallet until I notice it.

Instead of:

Dedicated server receiving 1 million hits per day from all around the world

You get ( example):

USA Node receiving 300,000 visits, European node receiving 250,000 visits, China node receiving 150,000 visits, African node receiving 150,000 visits and Australian Node receiving 150,000 visits.

Everyone gets the content faster and you get more clicks/conversions = more profit from your traffic.

Plus, you know anything can go wrong with your VPS or dedicated anytime and you might not be able to fix it ASAP. While if a node goes down on a CDN (very unlikely) the traffic gets routed to the nearest working node.

Often beginners ask us: Why should I use WordPress? Isn’t my old site good enough? Why do I need to switch to WordPress? If you’re asking these questions, then you’re at the right place. In this article, we have compiled a few reasons why you should use WordPress, in what ways you can use WordPress, and who is using WordPress.

Why You Should Use WordPress

People often make the mistake of classifying WordPress as just a blogging platform. Although that used to be true in the past, WordPress has evolved through out the years into a versatile content management system (CMS). While you can still use WordPress to create a simple blog, now it also allows you to create fully functional websites and mobile applications.

The best part about WordPress is that it’s easy to use and flexible enough for just about anything. That’s the main reason why WordPress has grown so much in popularity. According to a recent survey, WordPress powers 22.5% of all websites on the internet.

Due to it’s robust features, many of the top brands use WordPress to power their websites including but not limited to: Time Magazine, Google, Facebook, Sony, Disney, LinkedIn, The New York Times, CNN, eBay, and more.

Let’s take a look at why you should use WordPress.

WordPress is Free as in Freedom

WordPress is a free software, this means you are free to download, install, use and modify it. You can use it to create any kind of website. It is also open source which means the source code of the software is available for any one to study, modify and play with.

There are currently 2600+ WordPress themes and 31,000+ plugins available for free. You can download, install and use them on any website.

To run WordPress, all you need is a domain and web hosting. We recommend using either Bluehost or SiteGround because both of them offer our users a free domain and 50% off their hosting prices. Check out our guide on why is WordPress free?

WordPress is an open source software

Due to the nature of open source, WordPress is a community software. It is maintained by a large group of volunteers majority of whom are WordPress consultants with active interest in growing and maintaining WordPress. Anyone can contribute to WordPress by writing patches, answering support questions, writing plugins, creating themes, translating WordPress and updating documentation.

By using WordPress you become part of that awesome community. You get free support from other community members, download free plugins and themes, and once you have little experience with WordPress you can even contribute back to the community.

WordPress is Easy to Use and Learn

WordPress is easy to use even for beginners

WordPress is used by millions of people and almost every day new people are joining the WordPress community by creating their first WordPress powered websites. The reason why people quickly adapt to WordPress is because it is fairly easy to use.

Our website WPBeginner has tons of articles written specifically for beginner level WordPress users. We have a detailed step by step guide on how to install WordPress and hundreds of other WordPress tutorials.

If you want someone experienced to setup your WordPress site, then our talented staff members are happy to help you get started. The best part is that we offer a Free WordPress Blog Setup service.

For any WordPress related issue, you can search the web or search our archives, and you will definitely find help.

WordPress is Extendable by Using Themes and Plugins

WordPress Themes

Most people using WordPress are neither web designers nor programmers. As a matter of fact most folks start using WordPress without any prior knowledge of designing websites.

The reason why WordPress is such an ideal candidate is because there are thousands of free templates (themes) to choose from, so you can give your website any look you want. There is a WordPress theme for just about everything. Whether you want a photography theme, magazine theme, portfolio theme, or an eCommerce theme. There is a perfect theme available for every kind of website.

WordPress themes are easy to customize because a lot of them come with their own options panel allowing you to change colors, upload logo, change background, create beautiful sliders, and do other cool things with your website without ever writing any code at all.

WordPress is super flexible and can be extended by using plugins. Just like themes, there are thousands of free and premium plugins available for you to use (What is a plugin?). Not only these plugins can add extra functionality to WordPress, there are lots of plugins which can add a whole new platform to your WordPress site. Take a look at the plugins we are using on WPbeginner.

WordPress is Search Engine Friendly

WordPress is written using standard compliance high quality code and produces semantic mark up which makes your site very attractive to search engines.

By design WordPress is very SEO friendly, and you can make it even more SEO friendly by using WordPress SEO plugin. To understand you how to improve your site’s SEO check out our WordPress SEO tips for beginners.

WordPress is Easy To Manage

WordPress comes with built-in updater that allows you to update your plugins and themes from within your WordPress admin dashboard. It also notifies you when there is a new version of WordPress is available, so you can update it by just clicking a button. You can keep all your WordPress content safe by setting up automated regular WordPress Backups.

WordPress is Safe and Secure

WordPress is safe and secure

WordPress is developed with security in mind, so it is considered quite safe and secure to run any website. However, just like the real world, the internet can be an uncertain place.

There are intruders out there who want to get their hands on as many sites as they could. On our websites, we use Sucuri to monitor security threats and we highly recommend them.

WordPress Can Handle Different Media Types

WordPress can handle all your media files

Using WordPress you are not just limited to writing text. It comes with built-in support to handle images, audio, and video content. You can also use for document or file management.

WordPress supports oEmbed enabled websites which means you can embed YouTube videos, Instagram photos, Tweets, and Soundcloud audio by just pasting the URL in your post. You can even allow your visitors to embed videos in comments.

What ways to use WordPress?

WordPress can be used in many different ways. It is open to possibilities. Our site is not a blog, it is more of a business resource website, and we are running it on WordPress. You can use WordPress as the following:

Note that above are just some examples of how you can use WordPress. To see how other top businesses are using WordPress, visit the WordPress Showcase

We hope this article answered your question about why you should use WordPress. The best way to experience the true power of WordPress is by using it. Give it a try, and let us know what you think.

What is Web Development?

Web development is the process of developing websites or webpages hosted on the Internet or intranet. Think about your favorite website; whether it’s an e-commerce store, blog, social network, online video streaming service, or any other type of Internet application, it all had to be built by a web developer.

But what does that look like? The web development process can be divided into three main components: server-side coding, client-side coding and database technology.

Client-Side Coding

When you are viewing or using a website, you are known as a ‘user’ or a ‘client.’ So web applications or computer programs executed by a user’s web browser are referred to as client-side scripts. That means the program requests any files it needs to run from the web server, and then runs within the client’s web browser.

This allows a webpage to have unique and alternating content depending on a user’s input or other variables. Ajax, Flash, JavaScript, jQuery, Microsoft Silverlight, HTML5, and CSS3 are some examples of popular languages, plugins and libraries used in client-side scripting.

Server-Side Coding

In contrast to client-side scripts, server-side scripts are executed on the web server whenever a user requests a document or service. The server then produces the document, usually in the form of HTML, which can be read by the client’s browser.

The document sent to the browser may often contain client-side scripts. ASP.NET, PHP, Java, ColdFusion, Perl, Python, and Ruby are examples of languages used for server-side coding.

Database Technology

For any website to function on the Internet, it must be hosted within a database on a webserver. The database contains all the files required for a website and its applications to function. Websites typically use some form of a relational database management system (RDBMS); the leading RDBMS options are Oracle, Microsoft SQL Server, Apache, and IBM. Open-source RDBMS are also very popular, led by MySQL, PostgreSQL, and MariaDB.

 

So, if you want to make the Category whose ID number is 6 look different from what it is currently (and different from other Category pages), you would want to create a category-6.php file. If you want to make all Category pages look different from other archive pages (such as date and author archives), then you would want to create or modify the category.php file. If you want to make changes to the look of all archive pages, you can create or modify the archive.php file. And if you modify the index.php file, you will affect your entire blog.

Just Heading 2

Why choose Magento? Just ask our customers. The world’s biggest brands love Magento for its flexibility, because today’s consumers and their buying patterns are changing by the minute. Only Magento—open source and agile—can help you adapt and thrive. With a global ecosystem of 150,000 developers and a network of 300+ highly-trained solution partners, Magento boosts your online sales while maximizing gross margins. Magento businesses sell more at a lower TCO than merchants on competitive commerce platforms. Here’s how the Magento Advantage can work for you…

The World’s #1 Commerce Platform

Magento is the most popular commerce platform in the world, with more than 250,000 merchants around the globe selling more and driving innovation. Just check out our customer stories to find out how the Magento Advantage really works.

Stay Ahead of Customer Trends

Consumer behavior is changing every day. Today’s bleeding edge innovation will be tomorrow’s table stakes. Magento gives you the flexibility to customize and extend your platform to create unique, differentiated branded experiences. Adapt fast, and stay ahead of changing customer buying patterns. That’s the Magento Advantage.

An Army of Innovators

No IT team in the world can keep up with the changing face of commerce. With Magento, you get more than 150,000 innovators at your disposal. That’s an entire ecosystem of developers working hard to keep you ahead of the game and your competition.