All streams

Most startups are created by devotees who don’t really want to know about protecting their intellectual property. Often, this leads to unfortunate consequences. Here, I would like to give an overview of the most common errors — and how to avoid them.

Nuts and bolts

Patent is a document of title to:
• the exclusive right to,
• authorship and
• priority of an —
— invention,
— utility model, or
— industrial design.

Invention, in its essence, is a technical solution expressed in the combination of essential features — that are sufficient for achieving the technical result.

Essential features are those affecting the achievability of the technical result — or, in other words, are in a cause-and-effect relation with the result.

Technical result is a trait of the technical effect, event, property, etc. that effectively appear in the exercise of the method, or in the production or use of the product, including in the use of the product produced directly by the method, of invention.

Patent claim defines the scope of protection of the patent, as it comprises the combination of essential features — that are sufficient for achieving the technical result.

Error 1 — The lack of protection

Peter created an ingenious algorithm; there are no known analogues to that whatsoever. He fiercely codes a prototype and begins the commercialisation in Russia. He puts up a website, uploads a demo, does some exhibitions. Gains momentum and taps into the US market. And here we go…

There are a lot of different articles on Kalman filter, but it is difficult to find the one which contains an explanation, where all filtering formulas come from. I think that without understanding of that this science becomes completely non understandable. In this article I will try to explain everything in a simple way.

Kalman filter is very powerful tool for filtering of different kinds of data. The main idea behind this that one should use an information about the physical process. For example, if you are filtering data from a car’s speedometer then its inertia give you a right to treat a big speed deviation as a measuring error. Kalman filter is also interesting by the fact that in some way it is the best filter. We will discuss precisely what does it mean. In the end of the article I will show how it is possible to simplify the formulas.

Hi everyone!

This experimental article is translation of my Russian post (link). At the end of the year, I decided to think about what awaits the JS developer in the new 2019 year and to sum up this year.

Welcome to the cut!

I actively help companies from all over the world to prepare promotional content for English language resources. Today we will talk about common mistakes that are made by startups when working in this area and the erroneous expectations of their directors.

One of the many botched faxes

This is a (rather freely) translated version of this article.

When most people hear «fax», they remember those clumsy hybrids of a telephone and a printer straight outta 80s (unless you're in Japan, of course — they're still common there). But did you know that a similar technology is used to provide ship crews with weather data when there's no Internet connection? And Kyodo, a Japanese news agency (they sure like faxes, huh), still broadcasts news like that. And we can decode all this stuff, too — given a receiver, an audio cable and some software.

Last year 2018, a theatre production series called Tale of the Century was launched in Estonia. Throughout the year, 22 local theatres presented their interpretations of the past hundred years of Estonian history to the audiences. In the draw, the Russian Theatre was assigned the topic of the future of Estonia.

Did you ever think that one day you had got into PHP web programming too quickly?
Several years have passed already, you have gained a lot of experience and can’t think of any other ways to work with web but PHP. Perhaps, you sometimes doubt the choice you have made, but are unable to confirm your doubts here and now. At the same time, you need real examples; you want to understand the changes that may occur in particular aspects of your work.

Today I will try to answer the following question: "What if we use Python instead of PHP?".

I have asked this question myself many times. I have been using PHP for 11 years already and am a certified PHP specialist. I have mastered it so it works just the way I want. I was really puzzled by several articles that criticized PHP severely (PHP: a fractal of bad design). However, when chance came, I switched to Ruby and then to Python. Eventually, I chose the latter. Now I will try to explain how we Python guys live out there.

There are a lot of posts about what a typical coding interview at Google looks like. But, while not as widely described and discussed, there is also quite often a system design interview. For an SRE position it’s NALSD: non-abstract large system design. The key difference between SWE and SRE interviews consists in these two letters: NA.

So, what is the difference? How to be prepared for this interview? Let’s be non-abstract, and use an example. To be more non-abstract, let’s take something from the material world, such that you won’t be asked the exact same thing at the real interview (at least, not at the Google interview) :)

So, let’s design a public library system. For the paper books, like you have seen everywhere around. The whole text below was written all at once within around one hour, to roughly show you the areas that you should be able to cover / touch during the interview. Please excuse some disorder, that’s how I think (therefore I am).

In 2017, the media heard a very interesting story about a startup that robotizes milking cows on industrial dairy farms. The company is called R-SEPT, and back then it received 10 million rubles of investment. But a year has passed, and there's still no news on what happened further. We contacted Aleksey Khakhunov (AlexeiHahunov), the founder of the startup, and discussed the development. It turns out that the whole year his team was getting the prototype of the robot into shape, and just a week ago they conducted their first field test on the farm.

Under the cut there's a story about a robotics student who grew up on his parents' farm, turned the University diploma into an industrial startup, as he collected the first manipulators with his friends, and then scaled up to the level of state programs for the robotization of agriculture. And the most important is how the iron hand of the robot and the machine vision are better than a living milkmaid.

This is the first post in our blog in 2019. And this is important for all of us: we are finally launching the English version of Habr! Actually it was ready in the middle of December, but — you know — releasing a new feature right before Christmas is like deploying on Friday afternoon. So we decided to do it in the beginning of 2019.

Probably, there are not so many users on Habr who have never heard about the «Internet Archive», a service that searches and stores the digital data that is important for all mankind, whether it be the Internet pages, books, videos or other type of information.

Who manages the Internet archive, when it appeared and what is its mission? Read about it in the today's «Inquiry».

We all hear of iconic movies, games, books or musical compositions that get vehemently praised by the community of sophisticados, professionals and critics, yet never seem to attract tangible commercial success or the attention of the wider audience. Such situations leave me deeply frustrated.

When it comes to development, good tech also sometimes never gets into the limelight. Take F# for example. All I know about it is that it is a super-cool, yet totally unpopular language which makes it hard for developers – upon getting to know it – to get back to the languages they’re used to.

I tried to find out what is the story behind this. In fact, who are the people who use it and why are they doing this if the language is out of demand in business? To find answers, I joined the Russian-speaking F# community on Telegram – our round table for the discussion.

Hi there, Habr!

Remember the story of Steve Jobs and Dennis Ritchie? Without any intention to rekindle the debates or moralize on the subject, let’s face the truth: thousands of stellar techies live in the shadow, while their own stories are hidden in a dusty cupboard.

We, the Habr editorial team, are keen to tackle this injustice. From now on, we will regularly interview people who keep a low profile in media and social networks. So if you have anything to tell about yourself, get ready.

To give you an idea of what this will look like, we will lead the way. Click below to see 10 general questions we will ask every guest. For our pilot episode, the first guest to answer the questions was fillpackart. (This month I’ve had several quite good interview sessions with him, see articles one, two, three). Please read them, and if you make up your mind on telling your own story in a similar way, just send me or baragol a message.

Author of the original post in Russian: frsamara

I always loved playing with things and testing them under all sorts of wacky conditions as a kid and even considered getting a job as a tester, but I never did. Nevertheless, I still like taking things made by someone else and poking them for vulnerabilities.

I remember, when first self-service payment terminals started popping around town, I saw one of them put up a browser window while updating, and the game was on — I broke it almost immediately. There’s been a lot of discussion about it since then and developers have started to pay a lot more attention towards security in these machines.

Recently, fast-food joints have started installing these terminals. Obviously, it’s quite convenient: just tap a couple of virtual buttons, place an order, pay with a bank card and wait for your number to show on the screen.

Also, nearly every big mall has these interactive boards with floor plans and information on various sales and discounts.

How secure are they?

Author of the original post in Russian: varanio

You may have read a recent article suggesting that vim is great unlike IDEs, because of their allegedly low typing speed.

Let’s recall that the main message of that article was that vim’s killer feature consists in its modes that sort of outshine everything else. That said, the author acknowledged that IntelliJ IDEA and other IDEs provide hotkeys and other user experience which can be easily used. However, since they lack modes, vim is supposed to be everyone’s first choice.

The author then suggests that instead of pressing ctrl+arrows to move between words, it is easier to press Esc, e and then go back to the i editing mode. Understandably, all this trouble because the author finds it inconvenient to hold ctrl.

I know that articles that criticize vim get many negative votes, but I just have to speak out.

Author of the original post in Russian: old_gamer



I'm a ragman. I have a closet full of old hardware. From Boolean logic microchips in DIP-cases to Voodoo5. Of course, there's no practical value in all of this, but some people enjoy messing with old hardware. If you are one of them, I invite you under the cut, where I will tell you how the computer based on AMD 286 processor worked with a modern network, and what came out of it.

Author of the original post in Russian: HotWaterMusic

The history of the world's gamedev knows quite a few curious bugs that had to be tackled by developers. In fact, judging from the story that Media Molecule's CTO Alex Evans shared on his Twitter page this past weekend, many legends are still waiting to be heard. Evans is famous for his part in a demoscene performance of late 1990s and his work on the LittleBigPlanet game series and on Rag Doll Kung Fu.

The case I am referring to in this article took place ten years ago, in 2008. While working on the first part of LittleBigPlanet — an original puzzle platform video game that was to be released exclusively for PlayStation 3 — the company's developers came across a really hard-to-catch bug.

Normally, for a game to get the green light to be released for consoles, it needs to pass a certification process, i.e. meet a set of requirements predefined by the platform owner. The certification may also include more specific requirements, such as the game running smoothly without crashing for 24 hours.

The development of LittleBigPlanet was at its last stage, with just two weeks to final deployment and distribution. Suddenly a tester from the company's QA in Japan reported that the game was consistently crashing when left overnight. Now the release was evidently out of question unless the bug was fixed.

Иногда молодые команды разработки охватывает неразбериха.

Это случается в тот момент, когда они ещё не до конца разобрались, что такое эджайл; проджект и продакт спорят, кто из них кто, а задачи каждый ведёт сам по себе. Или все уже всё знают, но планировать спринты не получается — задачи не прорабатываются, демо и ретро проходят нерегулярно.

У нас тоже была похожая история, но мы нашли свой путь.

Это рассказ от команды личного кабинета Яндекс.Кассы, и подробнейшая инструкция для тех, кто хочет улучшить своё планирование.

Как всё было

Introduction

Our project implements a real-time edge detection system based on capturing image frames from an OV7670 camera and streaming them to a VGA monitor after applying a grayscale filter and Sobel operator. Our design is built on a Cyclone IV FPGA board which enables us to optimize the performance using the powerful features of the low-level hardware and parallel computations which is important to meet the requirements of the real-time system.

We used ZEOWAA FPGA development board which is based on Cyclone IV (EP4CE6E22C8N). Also, we used Quartus Prime Lite Edition as a development environment and Verilog HDL as a programming language. In addition, we used the built-in VGA interface to drive the VGA monitor, and GPIO (General Pins for Input and Output) to connect the external hardware with our board.

Introduction

As first-year students of Innopolis University, we had an opportunity to make our own project in computer architecture. University suggested us several projects and we have chosen to make a stack-based calculator with reverse polish notation. One of the requirements for the project is to use FPGA board provided by the university.



As our board, we have chosen Cyclon IV. Therefore, we had to write code on hardware description language. In the course we have studied Verilog, so we have chosen it. Also, the university has additional modules for FPGA, such as numpad, thus we decided to use it in our project.

In this article, we want to share our knowledge about FPGA and Verilog, also provide you with a tutorial to repeat our project.