• Delayed queue in Java and Redis

    • Translation

    Several years ago we had to solve how to enqueue events with an arbitrary delay, e.g. check a status of a payment 3 hours later, or send notification to a client in 45 minutes. At that point of time, we didn't find suitable libraries to accomplish this task, which didn't require us to spend time on configuration and maintenance. After analysing possible solutions we ended up building our own small library delayed queue in Java language on top of Redis storage engine. In this article I'll explain capabilities of this library, alternatives and problems we solved during creation process.

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  • How to verify Switching-Mode Power Supply circuits

    It is always good practice to verify a circuit before using.

    Switching-Mode Power Supplies are the most used circuits nowadays. But there are some difficulties with verifying their circuits: vendors do not publish models for all controllers; a model can be locked to be used with some tool; there may be errors in a model; average models want correct parameters and you need some practice of using them; transient models take a lot of time to get small-signal response and also may have errors.

    Let’s try to verify one circuit using my favorite electronics design tool “Circuit Calculator”.
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  • Tree Structure in EF Core: How to configure a self-referencing table and use it

    • Tutorial

    One of the very common questions I am getting from .NET community is how to configure and use the tree structures in EF Core. This story is one of the possible ways to do it.


    The common tree structures are file tree, categories hierarchy, and so on. Let it be folders tree for example. The entity class will be a Folder:


    public class Folder
    {
        public Guid Id { get; set; }
        public string Name { get; set; }      
        public Folder Parent { get; set; }
        public Guid? ParentId { get; set; }
        public ICollection<Folder> SubFolders { get; } = new List<Folder>();
    }
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  • 7 Ultimate Programming languages For Mobile App Development

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      Do you know that 21% of people open an app 50+ times per day? Yes, you heard that right. With the rapid development of technology, the mobile app now made many things possible, which was previously unthinkable.

      And that's why there is an incredible increase in the number of mobile users. According to a recent mobile app development stat, the number of mobile users worldwide is projected to increase to 6.95 billion by the end of 2020.

      In the last couple of years, the mobile app development industry has grown manifold, changing how businesses function around the world. If you are planning to jump into mobile app development, then choosing the right programming language will be the most significant challenge.

      There are more than 600 programming languages, and each one has its own perks and popularity. Are you pondering which language would be best for developing a stunning app?

      Several factors come to mind when making this choice, but the most important one is the language's demand. Here in this blog, I have listed the best programming language for mobile apps in terms of popularity and demand. Let's start!
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    • Don't spoil Desktop Software Engineers with your Mobile First solutions, think about it

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      English translation of Philip Ranzim's post at his blog page here. (With author's permission)


      Once upon a time, my girlfriend started using Instagram. She asked me to sign up for it and subscribe to it. I tried — I couldn't do it because you couldn't register at Instagram from a desktop computer. I then thought — how weird people are. Well, what kind of fool would make a software product that can't be used with a normal computer? They won't succeed, and this Instagram will be a marginal service for a bunch of strange women, who for some reason don't like desktops.


      It has only been a few years, the market has put everything in place — and the biggest fool was me. And the geniuses at Instagram predicted how and where everything would develop. Today, most of the user applications are made primarily for mobile platforms. At best, they include a universal web client, which is still optimized for mobile phones. Because users love iPhones, not computers. Business people sat down, counted, and made a decision — let's make more money, let's have mobile First everywhere.

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    • Static code analysis of the PMDK library collection by Intel and errors that are not actual errors

        PVS-Studio, PMDK

        We were asked to check a collection of open source PMDK libraries for developing and debugging applications with NVRAM support by PVS-Studio. Well, why not? Moreover, this is a small project in C and C++ with a total code base size of about 170 KLOC without comments. Which means, the results review won't take much energy and time. Let's go.
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      • How to save energy with BARY: Smart Home

        • Translation


        Well, every modern person has at least once wondered: for how much longer can you pay such huge utility bills?! I am no exception. Electricity, gas, heating, water, rent, elevator, removal of solid waste, etc. etc.

        One of the reasons (far from the last) of creating the BARY application was the ability to collect statistics, analyze and reduce energy consumption. Europe has long passed into the regime of total economy; I think this fate will not bypass us. Therefore, to prepare for this in advance definitely will not be superfluous.

        I now propose that we examine how we managed to optimize the cost of electricity along with BARY: Smart Home.
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      • AdBlock has stolen the banner, but banners are not teeth — they will be back

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        Ads
      • How to make your home ‘smart’ without going crazy

        • Translation
        image

        Smart furniture, which keeps your house in order, is a must for almost any futuristic set. In fact, an auto-regulating climate, automatic lights and voice control over household devices — all this can be done and configured now. But it will take a little experience, basic knowledge of technology and sometimes programming, as well as a whole sea of ​​fantasy. In my case, I did in the way that just fantasy will be enough, but first things first…
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      • Amazing Tactics to Improve Your Social Media Marketing Efforts

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          The benefits of a great social media strategy include increased brand awareness, customer loyalty, quality leads, and increased sales.

          However, these kinds of results are not easy to achieve.

          There’s fierce competition on social media and different ranking algorithms judging the content you post. Social media audiences also choose what content they deem relevant.

          You can no longer post content and hope that people will follow your account, engage with your content, and convert. Instead, you need to implement tactics that can help you gain market traction while enhancing your social presence.

          In this post, I’ll discuss some of the tactics you can implement to boost your social media marketing efforts.
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        • Future of AI in Education; Such a Great Revolution

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            This is the time when everyone is aware of the magic that AI is doing all over the world. Yes, it is true and no one can deny the fact that AI is ruling all over the world almost in all the fields and is making our lives more exciting and autonomous. Like other fields, it is playing an important role in the field of education.

            According to a survey, Artificial Intelligence (AI) recently started to penetrate into other industries in China. It was forecasted that by 2022 the Chinese market size of online education aided by artificial intelligence would amount to around 70.3 billion yuan.
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          • Using kconfig for own projects

              Intro


              Every Linux professional write scripts. Someеimes light, linear. Sometimes complex script with functions and libs(yes, you can write your bash-library for use in other scripts).


              But some of the scripts need a configuration file to work. For instance, I wrote a script that builds the ubuntu image for pxe, and I need to change the build process without build-script changes. The best way to resolve this task is to add configuration files.

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            • Modern COBOL: Package Tutorial

              • Tutorial

              You will learn and create an application-level library in COBOL. You will structure the package, implement automatic tests, deploy on GitHub and enable Continuous Integration workflow. Finally, you will publish the package in the COBOL package registry.

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            • Unicorns break into RTS: analyzing the OpenRA source code

                image1.png

                This article is about the check of the OpenRA project using the static PVS-Studio analyzer. What is OpenRA? It is an open source game engine designed to create real-time strategies. The article describes the analysis process, project features, and warnings that PVS-Studio has issued. And, of course, here we will discuss some features of the analyzer that made the project checking process more comfortable.
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              • IIoT platform databases – How Mail.ru Cloud Solutions deals with petabytes of data coming from a multitude of devices



                  Hello, my name is Andrey Sergeyev and I work as a Head of IoT Solution Development at Mail.ru Cloud Solutions. We all know there is no such thing as a universal database. Especially when the task is to build an IoT platform that would be capable of processing millions of events from various sensors in near real-time.

                  Our product Mail.ru IoT Platform started as a Tarantool-based prototype. I’m going to tell you about our journey, the problems we faced and the solutions we found. I will also show you a current architecture for the modern Industrial Internet of Things platform. In this article we will look into:

                  • our requirements for the database, universal solutions, and the CAP theorem
                  • whether the database + application server in one approach is a silver bullet
                  • the evolution of the platform and the databases used in it
                  • the number of Tarantools we use and how we came to this
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                • Как с помощью HUAWEI ML Kit самостоятельно создать апплет для фото на документы

                    Общая информация


                    В предыдущей статье мы рассказали о том, как создать камеру для улыбок с помощью HUAWEI ML Kit. В этот раз я собираюсь представить вам новую функцию HUAWEI ML Kit.

                    Вас когда-нибудь просили на учебе или работе принести фотографию определенного размера с цветным фоном для документов? В большинстве случаев у человека не окажется под рукой подходящей фотографии. Однажды в институте нам решили оформить персональные пропуска, но фотостудия оказалась закрыта. Тогда я сфотографировался на телефон, использовав простыню в качестве фона. И получил выговор от преподавателя. Но с помощью инструмента HUAWEI ML Kit вы сможете интегрировать SDK для сегментации изображений в ваше приложение и разработать апплет, чтобы создавать фото на документы самостоятельно и решить проблему отсутствия нужных фотографий.

                    Самое главное, что этот SDK абсолютно бесплатный и работает на всех телефонах на базе Android.

                    Разработка апплета для фото на документы самостоятельно


                    1. Подготовка


                    1.1 Добавьте репозиторий Maven Huawei в файл на уровне проекта build.gradle


                    Откройте файл build.gradle в корневом каталоге вашего проекта Android Studio.

                    image

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                  • What is a CRM system and how to choose it correctly

                    • Translation

                    In modern business the need of automation in various processes have already become commonplace. It is already becoming difficult to imagine a warehouse or accounting without the use of specialized software. The representatives engaged in trade use a special application for registration and sending the order to office directly from pads or mobile phones. Mostly the orders that are ordered from the website are delivered in the form ready for processing. But at the same time customer relationships, at least in the medium and small business for some reason, very often maintain without the integration of automation and sufficient attention to the account.

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                  • Neural networks in reality

                    The mass of news and articles about artificial intelligence creates the illusion that we are living in a fantastic time. But when you start asking everyone what exactly is useful in real life from these high technologies, the answers come down to some Google features, mobile games and a story about Chinese videos. By the way, oh, these Chinese videos — for some reason, they are constantly shown by the central mass media when they demonstrate Moscow's intellectual technologies.

                    In words, it seems, all the «intellects» are installed already everywhere, the whole country has long been transferred to neural networks, but only in some kind of demonstration pictures, in diagrams, on fingers. There is a mental dissonance — why not take a video camera and shoot at least a fragment of how Russia's super mega technologies work?

                    As Nikita Sergeevich said, «science ceases to be self-indulgence when its fruits are applied in the national economy.» And today's artificial intelligence is familiar to us only from games. Many people really want to see something useful in reality. Therefore, we were not too lazy and recorded our video of the operation of neural networks from real objects.

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                  • 11 Years Of Node.JS: Timeline & Significant Contributions

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                      Do you know Node.js has turned 11 on 27th May 2020? Can’t believe we have stepped into a new decade of this technology? Okay! Let me tell you the truth and story behind it with this article.

                      JavaScript has come a long way with its constant bombardment of open-source frameworks. We all have embraced its journey, and Node.js is one of its prevalent and predominant innovations that knocked this tech arena on May 27th, 2009. So, technically and mathematically, both Node.js is 11 years old now.
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                    • Top 5 Android App Development Companies To Seek in 2020

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                        The mobile app industry is at its peak of success and keeps evolving with the latest mobile app development technologies in future. It doesn’t matter which business you run but without an app, you cannot grow in this competitive environment.

                        An Android app is enough to make you achieve all your business goals. In 2019, there were around 2.13 billion apps downloaded from Google Play Store which clearly indicates its huge demand in near future and so the demand for Android app development companies in 2020.

                        According to AppBrain stats, there are over 2,963,573 Android apps on Google Play at present and approx. 1,365,868 no. of apps with rating.

                        image

                        With so many app development companies around us make it difficult to select the reliable Android app development company especially when it comes to business owners. Finding a cost-effective company which can give satisfactory results is not much difficult as it seems to you.

                        All you need to pick a sorted collection of the best Android app development companies where you can find the one which suits your business. Here, I have sorted a list of top 5 Android App Development Companies that you can partner with in 2020.
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                      • Sberbank Online iOS testing

                        • Tutorial
                        Theory of testing is usually differs from practice. Today we want to talk about our practical experience in testing application's code which is used by millions of iOS users and about the difficult path that our team finished in order to achieve stable code.

                        Let’s imagine: the developers successfully convinced themselves and the business of the need to cover the code with tests. Over time, in the project were created more than a dozen thousand unit- and more than a thousand UI-tests. Such a large test base araised several problems, and we successfully found the solution for them.
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