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Ray Cast Visual Search (RCVS). Fast and simple algorithm for searching 3D objects with similar shapes

Reading time8 min
Views3.1K
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For me, these two models are quite similar, but in fact they don’t have obvious characteristics to measure this similarity. These models have different numbers of vertices, edges and polygons. They are of different sizes, rotated differently and both have the same transforms (Location = [0,0,0], Rotation in radians = [0,0,0], Scale = [1,1,1]). So how to determine their similarity?
Total votes 3: ↑3 and ↓0+3
Comments0

buildroot — my own experience with multi-platform distro creation

Reading time5 min
Views5.5K

Introduction


In my previous article (Monitor linux) I wrote, what is this distro and how it works. Now i will write how to do it. It's may be interesting for everyone, who want to study buildroot.


Target goals


The result we get from article is the following:


  • Firmware (non-volatile image with restorable config)
  • Easy management via web-interface
  • Cross-platform (qemu x86_64, arm-based SBC like rasberry 4, beagle bone black and asus tinker board)
  • Support without extra effort
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Total votes 8: ↑6 and ↓2+4
Comments2

Discover Unmatched Potential of Java for Your Next App

Reading time3 min
Views720


One of the most popular programming languages for a decade, Java has been the top choice and preference of most software application development companies. More and more businesses are looking forward to leveraging the potential of the Java language. How can they not? The websites, web apps, mobile apps all could be developed easily using the language. From small, easy to complex apps, Java is the best-suited as it is robust, reliable, and user-friendly programming language.
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Rating0
Comments0

Ideas for Startups in 2020: 5 Distinct on-demand Mobile App

Reading time4 min
Views1.2K
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We have transcended into a world where most of the services that we want our needs available right in the comfort and confines of our homes! It is quite likely that an application addresses those needs.What makes these applications more interesting and relevant is the fact that they can identify the user and multiple attributes.

One of the significant attributes that can be identified by using mobile applications is the precise location of the user. The GPS, which was once confined to the military and aviation industry, has now been made available to almost every smartphone user. The GPS, combined with the mapping and navigation services by technology companies like Google and Apple, has made it extremely easy for the service provider to reach the location of the user.
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Total votes 5: ↑4 and ↓1+3
Comments1

Token2 C301-i, the first iOS-compatible programmable TOTP token

Reading time2 min
Views955
TOKEN2 started manufacturing and selling programmable hardware tokens back in 2015 and we have been constantly asked questions about iPhone support. So far, our burner apps were available only for Android and Windows, as Apple did not allow using the NFC protocol on their devices, even though the hardware supporting NFC was physically present.

iOS 13 — coreNFC


The situation has improved a little bit with the release of iOS v13 when access to more features of coreNFC Developer API was introduced. Unfortunately, we discovered that it is not fully compatible with the NFC chips we are using. As there are little chances that Apple will make an effort to change this to adapt to our NFC chips, we had to do the opposite and develop a new, iOS13 compatible, NFC chip instead.

Token2 C301-i, the first iOS-compatible programmable TOTP token


Our first iOS-compatible token (model reference: “C301-i”) is currently being beta-tested and will start selling in a couple of months. Pre-orders are available here.
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Total votes 1: ↑1 and ↓0+1
Comments0

What does «clean code» mean in 2020?

Reading time9 min
Views6.5K

«Clean Code» and a clean cat

There is nothing developers enjoy better than arguing about clean code: Dan Abramov, for example, has recently fueled the hype with his blog post, «Goodbye, Clean Code».

However, “clean code” per se doesn’t even have a clear definition. The main book on the subject is Clean Code, where Robert «Uncle Bob» Martin states that there are perhaps as many definitions as there are programmers. But he doesn’t walk away from the fact with a conclusion that there’s no reason to discuss clean code, rather — compare several definitions and highlight general ideas. Therefore he cites the views of several outstanding programmers on what clean code is.

So we have also become interested in what people in 2020 think of clean code. Have the views changed since the publication of the book? Do opinions vary in different IT fields (maybe backend developers perceive the idea of clean code differently from testers)?

This spring, Uncle Bob comes to St. Petersburg to give talks at our three conferences: they are about .NET development, testing and JavaScript. Therefore, we’ve asked speakers from each of those conferences to share their opinion on clean code so we could compare the opinions of the industry experts in 2020.

We've already published the results in Russian, and here's the English version. Since the topic is known to provoke discussions, feel free to give your own definition or argue about those already given!

UPD: When we posted this article, Uncle Bob had our conferences in his schedule. Unfortunately, the situation has changed. We updated this post on March 12, to avoid any misunderstanding.

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Total votes 10: ↑10 and ↓0+10
Comments0

Using Data Science for house hunting in Montreal

Reading time7 min
Views4.6K

Introduction


I happen to live in Montreal, in my condo on the edge of McGill Ghetto. Close to Saint Laurent Boulevard or the Maine as locals call it, with all it's attractions — bars, restaurants, night clubs, drunken students. And once upon a time, on a particular lively night, listening to the sounds of McGill frosh students drunkenly heading home after hard night of studying. I thought, that it might be a good idea to move into my own house, a little bit further away from the action.


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Total votes 10: ↑9 and ↓1+8
Comments0

Quick Sort Algorithm in JavaSript (pivot as the first element + pivot as the random element)

Reading time5 min
Views18K

Introduction


Quick Sort is one of the most famous and effective Sorting Algorithms. The comprehension of how it works will undoubtedly help you in your JavaScript learning. Also, questions on algorithms are popular in job interviews, so there is a big chance you will be asked to describe how Quick Sort works.

I’m sure that I convinced you that Quick Sort is important. Let’s start!


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Total votes 7: ↑5 and ↓2+3
Comments2

On recursive queries

Reading time25 min
Views10K
This article deals with writing recursive queries. This topic was brought up routinely, but the discussion was usually limited to simple cases related to trees: to descend from a vertex to the leaves and to ascend from a vertex to the root. We will address a more complicated case of an arbitrary graph.

Let's start with recalling the theory (very briefly since all of it is trivial), and then we will discuss what to do if it is unclear how to approach a real-life problem or if it seems to be clear, but the query persistently fails to work fine.

For an exercise, we will use the airlines demo database and try to write a query to find the shortest route from one airport to another.
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Rating0
Comments0

Mind traps: how scientists fool themselves

Reading time5 min
Views2.1K
Even the most honest of scientists are regularly misled by their cognitive biases. They often go to great lengths to find proof for whatever seems logical, while dismissing evidence to the contrary.

Yet this issue is rarely discussed — because it remains an embarrassing subject.

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Total votes 5: ↑4 and ↓1+3
Comments0

Eliminating Render-Blocking JavaScript and CSS on WordPress

Reading time4 min
Views1.4K

Outstanding loading speed is an essential website feature for a high ranking in SERP (Search Engine Result Pages). PageSpeed Insights by Google is an excellent tool for precisely that — optimizing your website’s loading speed. Let’s say you’re using this tool and get the “Eliminate render-blocking JavaScript and CSS in above-the-fold content” warning. No need to worry! In this tutorial, I will show you how to address the issue.

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Rating0
Comments0

3D Keyboard Key on CSS

Reading time3 min
Views1.8K

Introduction


People use their gadgets every day. And the main attribute of any gadget is a keyboard. But have you ever thought about creating a keyboard that would display on your screen?

In this article, we will create a 3D Keyboard Key with awesome animation after clicking on it. And yes, we will not use any programming language. Our key will be on the power of CSS! Let’s get started!

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Implementation

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Total votes 7: ↑3 and ↓4-1
Comments4

Are my open-source libraries vulnerable? (2 min reading to make your life more secure)

Reading time2 min
Views2.5K

The explosion of open source and issues related to it


The amount of open source or other third party code used in a software project is estimated as 60-90% of a codebase. Components, such as libraries, frameworks, and other software modules, almost always run with full privileges. If a vulnerable component is exploited, such an attack can facilitate serious data loss or server takeover. Applications using components with known vulnerabilities may undermine application defences and enable a range of possible attacks and impacts.



Conclusion: even if you perform constant security code reviews, you still might be vulnerable because of third-party components.

Some have tried to do this manually, but the sheer amount of work and data is growing and is time consuming, difficult, and error prone to manage. It would require several full time employees and skilled security analysts to constantly monitor all sources to stay on top.
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Total votes 6: ↑5 and ↓1+4
Comments2

Python-Celery in Windows with Docker managing

Reading time2 min
Views4.7K
To 'adequately' debug Celery under Windows, there are several ways such as:

> celery worker --app=demo_app.core --pool=solo --loglevel=INFO

But in fact for normal development, you need a Unix system. If you do not have the opportunity to use it as a native, then it is worth considering...) Well, to be honest, there is always a way out and this is Docker and WSL. If you use such “cool” IDEs like PyCharm, then everything becomes more complicated, because using the WSL interpreter, installing the package with pip, you will have to manually update the project skeleton due to indexing problems.
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Total votes 5: ↑4 and ↓1+3
Comments0

Fault Tolerance Web Architecture for Our Cloud Solutions

Reading time10 min
Views3K
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Hi Habr,

I'm Artyom Karamyshev, a system administration team leader at Mail.Ru Cloud Solutions (MCS). We launched many products in 2019. We've aimed to make API services easily scalable, fault-tolerant, and ready to accommodate rapid growth. Our platform is running on OpenStack, and in this article, I describe all the component fault tolerance issues that we've resolved.

The overall fault tolerance of the platform is consists of its components fault tolerance. So, I'm going to show you step by step tutorial about all levels where we've found the risks.
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Total votes 25: ↑24 and ↓1+23
Comments0

How 5G's Acceleration will move through the Mobile App Development Space?

Reading time6 min
Views1.2K
5G ( Fifth Generation Wireless Cellular Network) is not just a possibility anymore. The forthcoming of 2020 has unfold avenues for 5G browser capabilities in smartphones.

With the recent 5G rollout, it has been predicted that over 1.4 billion devices will be running on the 5G network by 2025 — accounting for 15% of the global total.

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Source: Google Images
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Total votes 10: ↑8 and ↓2+6
Comments0
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