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The Department of Computer Science and Control Systems at ITMO University houses a robotics lab. In this article we’ll take a look at the projects its staff is working on, and show you the machinery on site: industrial manipulator robots, robotic hands and dynamic positioning system testing equipment.

This is a guest post from the Orleans team. Orleans is a cross-platform framework for building distributed applications with .NET. For more information, see https://github.com/dotnet/orleans.

We are excited to announce the Orleans 3.0 release. A great number of improvements and fixes went in, as well as several new features, since Orleans 2.0. These changes were driven by the experience of many people running Orleans-based applications in production in a wide range of scenarios and environments, and by the ingenuity and passion of the global Orleans community that always strives to make the codebase better, faster, and more flexible. A BIG Thank You to all who contributed to this release in various ways!

Chapter 2.
(the link to Chapter 1)

The Art of Designing Road Networks

Transport problems of a city through the eyes of a Computer Scientist

If I were recommended an article with the title “The Art of Designing Road Networks,” I would immediately ask how many road networks were built with the participation of its author. I must admit, my professional activity was far from road construction and was recently associated with the design of microprocessors where I, among other responsibilities, was engaged in the resource consumption of data switching. At that time my table stood just opposite the panoramic window which opened up a beautiful view of the long section of the Volgograd Highway and part of the Third Transport Ring with their endless traffic jams from morning to evening, from horizon to horizon. One day, I had a sudden shock of recognition: “The complexities of the data switching process that I struggle with on a chip may be similar to the difficulties the cars face as they flow through the labyrinth of road network”.
Probably, this view from the outside and the application of methods that were not traditional for the area in question gave me a chance to understand the cause of traffic jams and make recommendations on how to overcome the problem in practice.

Attackers and defenders to face off in digital metropolis security challenge featuring real-world critical infrastructure and technologies.



Cybersecurity experts at Positive Technologies and Hack In The Box are inviting red and blue team security specialists to test their skills attacking and defending a full-scale modern city at The Standoff Cyberbattle held during HITB+ CyberWeek. This mock digital metropolis with full IT and OT infrastructure including traffic systems, electrical plants, and transportation networks will feature all the latest technologies used in actual critical infrastructure installations, allowing players to expose security issues and the impact they might have on the real world.

There is a good practice to make your application beautiful and live, and nowadays there are a lot of tools and ways to achieve this. One of them is Shared Element Transition.

In this article I’ll cover a few mistakes which have cost me a lot of time; I’ll show how to avoid them if you decide to implement this kind of transitions with Fragments on application.

There’s a problem we needed to address in the course of developing our games. It’s complicated to generate a random number in a distributed network. Almost all blockchains have already faced this issue. Indeed, in networks where there is no trust between anyone, the creation of a random number solves a wide range of problems.

In this article, we explain how we solved this problem for our games. The first of these was Waves Xmas Tree.

I notice that people often use construction like this:

var length = array.Length;
for (int i = 0; i < length; i++) {
    //do smth
}

They think that having a call to the Array.Length on each iteration will make CLR to take more time to execute the code. To avoid it they store the length value in a local variable.
Let’s find out (once and for all !) if this is a viable thing or using a temporary variable is a waste of time.

We are beyond excited to announce Windows Terminal! Windows Terminal is a new, modern, fast, efficient, powerful, and productive terminal application for users of command-line tools and shells like Command Prompt, PowerShell, and WSL.

Windows Terminal will be delivered via the Microsoft Store in Windows 10 and will be updated regularly, ensuring you are always up to date and able to enjoy the newest features and latest improvements with minimum effort.

When you have an idea of a new game mechanic, or even flash of interesting concept — soon you'll be obsessed about it with an immense urge to start doing something already. Sometimes you write such ideas down somewhere and bring them a chance to ignite full development cycle later. But I've stumbled upon the opposite action. My current game became this giant monster eating finance and time, and grown much bigger than I ever thought. So, I've needed to put it back for a while. But I could not sit without game development, and in my free time I've started to work on my new project! Plus that one was quite different from the previous ones, because I've decided to target mobile. If you are interested in how this project was done, from a small idea to the final release, then let's dive into it!

I would like to share main points of my Skolkovo application for Startup Village 2019 pitch.

Indibiome labs

Project Executive Summary indicating current developments and basic goals of the Project

Indibiome labs for kids are franchise network food labs providing safe environment where kids (13+) will learn how to analyse the food content and study influence of foods on health and will spread this knowledge through social networks, therefore educating other kids and adults in the field of healthy nutrition.



1. Transporting prototypes

The idea of the DO-RA project originated in March 2011 after a nuclear disaster on the Fukushima Daiichi nuclear power plant in Japan. This gadget was conceived as a personal dosimeter/radiometer working with eponymous software (DO-RA.Soft) on mobile platforms (iOS, Android, WP) as well as on desktop platforms—Windows/Linux/MacOS.

At the end of 2017, a tourist from China brought in his backpack ten long-awaited prototypes from the DO-RA.Q test batch. They were manufactured in China based on our design documents and then transported from Shenzhen to Moscow. By the way, the development of design documents was assigned to the largest Design Centre in Eastern Europe—the PROMWAD company. The documents were clear and plain—prepared in IPC format and written in proper English—to enable the automated production of electronic devices in a foreign country.

Looking for an app development company? I’ve searched for information about it and made this list. It might help to find an app development company to hire. The list contains basic information about each company included in it like company size, hourly rate, min. project size, etc. And I recently decided to upgrade the list to 100 app development companies.

In this article, I decided to describe how the functionality of selecting and displaying photos on a specific place on the map was implemented in our photo service gfranq.com. The photo service does not work now.

Since we had a lot of photos in our service and sending requests to database every time the viewport changes was too resource-intensive, it was logical to divide the map into several areas that contain information about the retrieved data. For obvious reasons, these areas have rectangular shape (although hexagonal grid was considered too). As the areas become more spherical at large scales, elements of spherical geometry and tools for it were also considered.

In this article, the following issues were raised:

• Storing and retrieving photos from the database and caching them on the server (SQL, C#, ASP.NET).
• Downloading necessary photos on the client side and saving them to the client cache (JavaScript).
• Recalculation of photos that must be hidden or shown when the viewport changes.
• Elements of spherical geometry.

ML.NET is an open-source and cross-platform machine learning framework (Windows, Linux, macOS) for .NET developers. Using ML.NET, developers can leverage their existing tools and skillsets to develop and infuse custom AI into their applications by creating custom machine learning models for common scenarios like Sentiment Analysis, Recommendation, Image Classification and more!.

Today we’re announcing the ML.NET 1.0 RC (Release Candidate) (version 1.0.0-preview) which is the last preview release before releasing the final ML.NET 1.0 RTM in 2019 Q2 calendar year.

Soon we will be ending the first main milestone of a great journey in the open that started on May 2018 when releasing ML.NET 0.1 as open source. Since then we’ve been releasing monthly, 12 preview releases so far, as shown in the roadmap below:

In this release (ML.NET 1.0 RC) we have initially concluded our main API changes. For the next sprint we are focusing on improving documentation and samples and addressing major critical issues if needed.

The goal is to avoid any new breaking changes moving forward.

The last decades the world economy regularly falls into this vortex of financial crises that have affected each country. It almost led to the collapse of the existing financial system, due to this fact, experts in mathematical and economic modelling have become to use methods for controlling the losses of the asset and portfolio in the financial world (Lechner, L. A., and Ovaert, T. C. (2010). There is an increasing trend towards mathematical modelling of an economic process to predict the market behaviour and an assessment of its sustainability (ibid). Having without necessary attention to control and assess properly threats, everybody understands that it is able to trigger tremendous cost in the development of the organisation or even go bankrupt.

Value at Risk (VaR) has eventually been a regular approach to catch the risk among institutions in the finance sector and its regulator (Engle, R., and Manganelli S., 2004). The model is originally applied to estimate the loss value in the investment portfolio within a given period of time as well as at a given probability of occurrence. Besides the fact of using VaR in the financial sector, there are a lot of examples of estimation of value at risk in different area such as anticipating the medical staff to develop the healthcare resource management Zinouri, N. (2016). Despite its applied primitiveness in a real experiment, the model consists of drawbacks in evaluation, (ibid).

The goal of the report is a description of the existing VaR model including one of its upgrade versions, namely, Conditional Value at Risk (CVaR). In the next section and section 3, the evaluation algorithm and testing of the model are explained. For a vivid illustration, the expected loss is estimated on the asset of one of the Kazakhstani company trading in the financial stock exchange market in a long time period. The final sections 4 and 5 discuss and demonstrate the findings of the research work.

As Senior Software Engineer at company building messaging platform for healthcare industry I am responsible, including other duties, for performance of our application. We develop pretty standard web-service using Ruby on Rails application for business logic and API, React + Redux for users' facing single page application, as database we use PostgreSQL. Common reasons for performance problems in similar stacks are heavy queries to database and I would like to tell the story how we applied non-standard but fairly simple optimisations to improve performance.

Our business operates in US, so we have to be HIPAA compliant and follow certain security policies, security audit is something that we are always prepared for. To reduce risks and costs we rely on a special cloud provider to run our applications and databases, very similar to what Heroku does. On one hand it allows us to focus on building our platform but on the other hand it adds an additional limitation to our infrastructure. Talking shortly — we cannot scale up infinitely. As a successful startup we double number of users every few month and one day our monitoring told us that we were exceeding disk IO quota on the database server. Underlying AWS started throttling which was resulting in a significant performance degradation. Ruby application was not capable to serve all incoming traffic because Unicorn workers were spending too much time awaiting for database's response, customers were unhappy.

Dmitry Pichulin, known under the nick «deemru», won the game Fhloston Paradise, developed by Tradisys on the Waves blockchain.

The winner of Fhloston Paradise was supposed to be the player paying the very last stake during a 60-block period, before any other player could pay their stake and reset the counter to zero. The winner would collect all stakes paid by other players.

Dmitry's winning recipe was the bot Patrollo, which he created. The bot paid just eight 1 WAVES stakes for Dmitry and eventually won him 4,700 WAVES ($13,100). In this interview, Dmitry discusses his bot and prospects of blockchain games.

For Russian speaking posted translated version here.

This is how Alex Viscreanu’s talk on Moscow Python Conf++ named. Now it's two weeks till before the conference, but of course, I've already heard what Alex will speak about. Find below some spoilers and talk preparing backstage: what kind of an open source Zoo developed in Kiwi, how it tests Python code and what’s the difference between The Zoo and for example mypy.

— Tell us a bit about Kiwi, yourself and what is your work within a company?

Kiwi.com is an online travel agency based in Czech Republic. We aim to make travelling as simple and accessible as possible. The company was founded in 2012 as Skypicker, and since then it has become one of the five biggest online sellers of airline tickets in Europe. It was renamed to Kiwi.com in 2016.

The special feature that we, at Kiwi.com, offer is the virtual interlining, which allows us to connect flights from companies that don’t usually cooperate together, and we are covering the possible connection issues caused by delayed flights.

Some of the numbers that we manage at Kiwi.com include 90 000 000+ daily searches, 25 000 seats sold daily, and a total of 15 000 000 000+ flight combinations available.

Navigation in developing Android apps is quite important and you should think twice what library suits (or your own solution) most and how it will be convenient to use when the app becomes bigger. Also, it might be good to think about how easy it will be to change your implementation to another one.

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Every old hardware enthusiast has a fetish. In the eastern Europe it's often a clone of Sinclair ZX Spectrum, as they were extremely popular there, as well as in Britain and Spain though. Unfortunately, ZX Spectrum left very little legacy. IBM PC 5150 is a different beast. Many love this computer for its heritage. For it has eventually became an ultimate PC. The PC. But although the history of this computer is very well known, surprisingly enough not many people know what was under the bonnet of the very first IBM PC.