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Affordable as a Bus, Comfortable as a Taxi: A Promising Type of Public Transport for Large and Medium-Sized Cities.Part3

Level of difficulty Medium
Reading time 32 min
Views 299
Algorithms *Mathematics *Transport The future is here Urbanism
Opinion
Translation


Translation provided by ChatGPT, link to the original article in Russian

Link to Part 1: «Preliminary Analysis» (ру / eng )
Link to Part 2: «Experiments on a Torus» (ру / eng )
Link to Part 3: «Practically Significant Solutions» (ру / eng )
Link to «Summary» (ру / eng )

1 Playing Diplomacy


1.1 What this work is about


You're reading the third and final article in a series dedicated to minibus route schemes that would allow you to travel reasonably quickly, inexpensively, and most importantly, without any transfers, from any intersection to any other within a large city. You'll see many graphs, formulas, and figures below, but before we get to the technical part, I'd like to discuss the challenge of implementing this idea and invite you to participate in solving it.

1.2 A puzzle for the talented and brave (Eccentrics are welcome: 🎶)


I propose an adventure,
I propose a game,
I propose that you become part of a positive change in the lifestyle of almost a billion people around the planet,
I can't do this alone.
To start, I need your help with the following:
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Total votes 4: ↑3 and ↓1 +2
Comments 4

How to set up Gitlab CI/CD with Fastlane for iOS-project on a Mac mini

Reading time 8 min
Views 222
Doubletapp corporate blog Habr Development for iOS *
Tutorial

Hello, everyone! I’m Yaroslav Fomenko, Doubletapp iOS-developer. Since the end of May, my department colleague and I have been working on implementation, improvement, and scaling of CI/CD for our projects. In this article, we want to share a guide on preparing the Xcode project and setting up runners, scripts, and configs, as well as explain how CI/CD helps us.

To learn how and why we decided to use a Mac mini for CI/CD, click here.

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Total votes 1: ↑0 and ↓1 -1
Comments 0

CI/CD for iOS-projects: device or cloud? What’s better, Doubletapp’s take

Level of difficulty Medium
Reading time 6 min
Views 190
Doubletapp corporate blog Habr Development for iOS *
Review

Hey, Habr! I’m Yaroslav Fomenko, Doubletapp iOS-developer. After our IOS department deployed our CI/CD on a Mac Mini, we got an idea of scaling and encapsulating it. So we started researching ways to do it. First we thought of Docker, but there was neither enough info about it nor any other possible ways. In this article, we’ll look at all possible solutions we found for the deployment of Gitlab CI/CD on a device and in the cloud.

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Total votes 1: ↑0 and ↓1 -1
Comments 0

The Growing Field of Fraud Prevention: Insights and Career Opportunities

Reading time 4 min
Views 97
Payment systems *IT career Finance in IT
Opinion

Hi Everyone,

I would like to draw your attention to some key insights from two comprehensive reports, shedding light on the importance of fraud prevention as a burgeoning field with substantial job prospects. The original reports can be accessed through the link provided at the end of this message.

Firstly, let's consider a couple of significant events from the previous year that remain highly relevant. Retail e-commerce sales surged to a staggering $5 trillion, with projections indicating a further increase to $8 trillion by 2026. Furthermore, the percentage of shoppers making cross-border purchases rose from 69% in 2019 to an impressive 76%.

These statistics affirm that online shopping is not a passing trend, as consumers are willing to make purchases from international vendors, even if it means enduring longer delivery times in exchange for lower prices. From a fraud prevention perspective, this highlights the escalating number of non-domestic payments and the rise in the use of lost or stolen cards for purchasing goods that can be resold in the future. Notably, refund fraud is becoming increasingly prevalent. However, many businesses have adapted their protocols to accommodate these emerging challenges. One such positive development is the gradual disappearance of restrictions on using payment methods that do not match the account country.

As cross-border purchases continue to proliferate, alternative payment methods are also on the rise. Current global statistics indicate that an average of four payment options are now available on merchant platforms. Additionally, open banking payment transactions are projected to surpass $330 billion globally by 2027, leading to a greater diversity of alternative payment methods. As companies embrace these methods, they are also becoming more aware of the associated risks. For instance, direct banking payment methods present unique challenges as they lack refund capabilities, while Buy Now Pay Later (BNPL) options introduce their own set of risks.

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Affordable as a Bus, Comfortable as a Taxi: A Promising Type of Public Transport for Large and Medium-Sized Cities.Part2

Level of difficulty Medium
Reading time 56 min
Views 301
Algorithms *Mathematics *Transport The future is here Urbanism
Opinion
Translation

(Jean-Claude Mézières)

Translation provided by ChatGPT, link to the original article in Russian

Link to Part 1: «Preliminary Analysis» (ру / eng )
Link to Part 2: «Experiments on a Torus» (ру / eng )
Link to Part 3: «Practically Significant Solutions» (ру / eng )
Link to «Summary» (ру / eng )

Experiments on the Torus


This is the second part of a study dedicated to exploring new public transportation movement schemes. In the first part, we examined the simplest non-stop scheme and a single-transfer scheme based on it, which can be implemented in a grid city on a plane. In this part, our city model will be a grid city on a «flat» torus. Unlike a rectangle, a torus has no edge, and the positions of all points on it are absolutely equivalent. Due to the absence of an edge and (transitive) symmetry, calculations for a toroidal city are simpler, and numerical results are nearly identical to those for a rectangular city on a plane. These two conditions make a toroidal grid city an ideal testing ground for new passenger transportation movement schemes. In this article, we will explore two such schemes on the torus, and in the next one, we will return to the plane and adapt the results obtained here for use under the realistic conditions of a rectangular city.

The content of this study is not standalone and presupposes familiarity with the first part of the article. To understand Chapter 2, you will need a level of mathematics that corresponds roughly to the first two years of university; for everything else, high school level should suffice. It can be helpful to have a pencil and a piece of paper at hand while reading. If your browser displays formulas incorrectly, try refreshing the page a few times.
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Total votes 3: ↑3 and ↓0 +3
Comments 0

How did I increase the website performance score from 35 to 100 for both mobile and desktop?

Level of difficulty Easy
Reading time 5 min
Views 227
High performance *Website development *JavaScript *Firebird/Interbase *ReactJS *
Sandbox

Not long ago, I started my personal blog. Instead of opting for the traditional route of using the popular WordPress CMS for blogs, I decided to embrace new technologies. My choice landed on Next.js and a NoSQL-type database.

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Total votes 1: ↑1 and ↓0 +1
Comments 0

Uniform gravity, can it exist?

Level of difficulty Medium
Reading time 3 min
Views 115
Popular science Physics
Analytics

Uniform gravity, can it exist?

1. The motion of a free particle-like cat

V. Komen, I. Tikhonenkov

Good morning! You've woke up. Having prepared coffee and toasts of bread you are drifting from a kitchen to a table before a large wall TV. The left hand keeps a small plate with toasts and the right one controls coffee level within your beloved mug. The life is plotted out for ten seconds to come. But Ervin is already worried that you, as usual, made conspiracy and decided not to share your breakfast with him. So the damned cat thrusts himself across you pass, hits your legs. By the next moment the plate, toasts and the mug are falling. And – yes! All those precious things reached a floor level by the same time. Physics...It's how it shows up, unexpected. And we used to identify ourselves as physicists. The unexpected thing is that we still do. It's whence our motivation originates. We cannot pass by any falling objects quietly.

15
Rating 0
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Affordable as a Bus, Comfortable as a Taxi: A Promising Type of Public Transport for Large and Medium-Sized Cities.Part1

Level of difficulty Medium
Reading time 40 min
Views 893
Algorithms *Mathematics *Transport The future is here Urbanism
Opinion
Translation

(Jean-Claude Mézières)

Translation provided by ChatGPT, link to the original article in Russian

Link to Part 1: «Preliminary Analysis» (ру / eng )
Link to Part 2: «Experiments on a Torus» (ру / eng )
Link to Part 3: «Practically Significant Solutions» (ру / eng )
Link to «Summary» (ру / eng )

1. About this series of articles


1.1 Central result


If I haven't made a critical mistake, I have discovered an astonishing passenger transportation scheme with unique characteristics. Imagine this scenario: you are in a big city and need to get from point A to point B. All you need to do is walk to the nearest intersection and indicate the destination on your smartphone or a special terminal installed there. In a few minutes, a small but spacious bus will arrive for you. The bus is designed for easy entry without bending, and you can bring a stroller, bicycle, or even a cello inside. It provides comfortable seating where you can stretch your legs. This bus will take you to the nearest intersection to point B, and you will reach your destination without any transfers. The entire journey, including waiting at the stop, will take only 25-50% more time than if you were traveling by private car. Based on my estimation, in modern metropolises, this type of transportation will be widely adopted, and the cost of a trip on such buses will be similar to the fare of a regular city bus.

Surprisingly, the reasoning behind these findings is based on relatively simple mathematics, and perhaps even a talented high school student, under fortunate circumstances, could have guessed them on their own. The practical significance of the topic and the modest level of mathematical requirements prompted me to make an effort to write the article in such a way that the reader could follow the path of discoveries, learn some research techniques, and gain a successful example to explain to their children the purpose of mathematics and how it can be applied in everyday life.
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Total votes 9: ↑7 and ↓2 +5
Comments 6

Pixel image rotation

Level of difficulty Easy
Reading time 13 min
Views 427
C *Data Engineering *

Brief problem formulation

The program accepts as input the absolute path to the image in the bmp extension and the path where you save the result of the work. Then, it rotates the image by 90 degrees counterclockwise. Afterwards, the program saves the new image.

The program is executed on C.

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Total votes 7: ↑5 and ↓2 +3
Comments 0

How we built a Cyber Immune product using an open source library: stages, pitfalls, solutions

Reading time 11 min
Views 201
«Лаборатория Касперского» corporate blog Information Security *Open source *Programming *
Translation
Do you remember how, even before the pandemic set in, companies were striving to provide secure perimeter access for their telecommuters? Especially if super sensitive data was involved such as accounting information or corporate documents. The solutions were complex, bulky and expensive. Can you imagine just how critical it has become now?!

image

My name is Sergey Yakovlev, and I'm the head of the Kaspersky Thin Client project based on our proprietary operating system, KasperskyOS. A thin client is one of the main components of a virtual desktop infrastructure, which is a remote desktop access system. In this article, I will use such a client as an example of how you can build a secure (yet commercially viable!) product. I will cover the stages, the stumbling blocks, the problems and solutions. Let's go!
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Rating 0
Comments 0

PostgreSQL 16: Part 5 or CommitFest 2023-03

Level of difficulty Medium
Reading time 28 min
Views 279
Postgres Professional corporate blog PostgreSQL *SQL *
Digest
Translation

The end of the March Commitfest concludes the acceptance of patches for PostgreSQL 16. Let’s take a look at some exciting new updates it introduced.

I hope that this review together with the previous articles in the series (2022-072022-092022-112023-01) will give you a coherent idea of the new features of PostgreSQL 16.

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

«Promising Public Transportation for Large and Medium-Sized Cities» — the main idea in a brief summary

Level of difficulty Easy
Reading time 9 min
Views 466
Algorithms *Mathematics *Transport The future is here Urbanism
Opinion
Translation

(source)

Translation provided by ChatGPT, link to the original article.

I recently published a series of articles titled 'As Cheap as a Bus, as Convenient as a Taxi...':

Link to Part 1: «Preliminary Analysis» (ру / eng )
Link to Part 2: «Experiments on a Torus» (ру / eng )
Link to Part 3: «Practically Significant Solutions» (ру / eng )

dedicated to making public transportation in large cities completely seamless, without the need for transfers. In the last article of the series, I extensively described a microbus movement scheme that allows them to operate almost like taxis while accommodating 5-10 passengers at once. Such a transportation system would enable city residents to travel from any intersection to another without any transfers, comparable in time to a personal car journey, and at a cost similar to a regular city bus ticket. However, the feedback from readers indicated that I chose an extremely ineffective way to convey the information, resulting in a failure to effectively communicate the essence of the matter.

I must admit that the previous three articles were written in a way that allowed readers to apply the acquired knowledge in practice or continue the research I started on their own. Unfortunately, my desire to 'teach' resulted in nearly 100 pages of complex mathematical text, which is clearly excessive for readers who simply wanted to familiarize themselves with the idea. Here, I will attempt to rectify this mistake and briefly, yet simply, explain the bus taxi technology.
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Total votes 6: ↑6 and ↓0 +6
Comments 0

Blinking into Morse code

Level of difficulty Easy
Reading time 10 min
Views 371
Python *IT Infrastructure *Data Engineering *
Sandbox

Explaining main algorithm.

For a while I’ve been thinking of writing a scientific article. I wanted it to have certain utility.

Morse code is binary: it takes only two values – either dot (short) or hyphen (long). I figured out that short (s) can stand for two-eye blinking whilst long (l) can indicate left-eye blinking. Another question emerged: how to understand when does one-symbol recording stop?

Empty space between two symbols can be presented by right-eye blinking – r. If I input singly symbol of short (dot) and long (hyphen), I will blink my right eye once to indicate the space between two symbols.

To separate independent words, one has to blink her right eye twice and get rr.

Hence, I have collected an ordered set of symbols – r, l, s, - that can be converted into a full-fledged text. Once I accomplish the transformation, I get an answer.

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Total votes 6: ↑6 and ↓0 +6
Comments 2

Feature Engineering: Techniques and Best Practices for Data Scientists

Reading time 8 min
Views 392
Big Data *Data Engineering *
Tutorial

The most important stage in the data science process is feature engineering, which entails turning raw data into useful features that might enhance the performance of machine learning models. It calls for creativity, data-driven thinking, and domain expertise. Data scientists can improve the prediction capability of their models and find hidden patterns in the data by choosing, combining, and inventing relevant features. Handling missing data, scaling features, encoding categorical variables, constructing interaction terms, and other procedures are examples of feature engineering techniques. The best practises involve investigating the data, testing and improving features iteratively, and applying domain knowledge to draw out important information. The accuracy and effectiveness of machine learning models are significantly influenced by effective feature engineering.

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Technical Game Design. Configs, balance and content in the example of PC strategy

Level of difficulty Medium
Reading time 13 min
Views 356
Game development *Unity3D *Game testing *Unreal Engine *Game design *
Case
Translation

One of the common tasks that both beginners and experienced game designers face is describing a large amount of content to pass its parameters to the engine. This is not an easy task, given that it is very difficult to find materials on the technical aspects of game design. Well, let’s figure out how to transfer data to the engine.

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Total votes 2: ↑2 and ↓0 +2
Comments 0

Push notifications: why we need them, how to do them. How to write push notifications that won't piss you off

Level of difficulty Easy
Reading time 11 min
Views 460
Internet marketing *Display advertising *Mobile App Analytics *Gadgets

Push notifications are similar to promoters. You're peacefully walking down the street, and suddenly promoters approach you, urging you to take their flyers. You take them, but you don't read them and throw them into the nearest trash can.

The same goes for push notifications. You're reading an article, and suddenly a notification pops up with a promo code for free delivery of products. Then another one arrives, informing you about a giveaway. And then another one, offering a discount on all fruits. Notifications can appear on your screen at any time. If there are too many of them, your reaction is either to ignore them or disable them.

In this article, we will talk about how to write push notifications that people will click on and show you how to build a push notification strategy. At the end, we will provide a template for a push notification strategy.

Push Notifications - What is it?

A push notification is a pop-up message on a smartphone screen. To send one, you need to use a delivery service. You can send a notification instantly, schedule it for a specific time, or set up a trigger-based delivery - a chain of notifications that will be triggered by specific user actions.

Triggered push notifications are sent after a specific action is taken. For example, if a person starts adding items to their cart but doesn't complete the purchase, you can send them a notification urging them to complete the transaction after a certain period of time.

Notifications are sent to users who fall into specific segments for targeting. Segments are formed based on specific events. For example, the event "6 hours ago, a product was added to the cart but no purchase was made" will divide users into two segments: those who made a purchase and those who didn't.

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Total votes 4: ↑4 and ↓0 +4
Comments 1

Monitoring CPU/RAM/disk metrics with OpenTelemetry and Uptrace

Level of difficulty Easy
Reading time 4 min
Views 822
Open source *
Tutorial

OpenTeleletry Collector is an open source data collection pipeline that allows you to monitor CPU, RAM, disk, network metrics, and many more.

Collector itself does not include built-in storage or analysis capabilities, but you can export the data to Uptrace and ClickHouse, using them as a replacement for Grafana and Prometheus.

When compared to Prometheus, ClickHouse can offer small on-disk data size and better query performance when analyzing millions of timeseries.

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Total votes 6: ↑6 and ↓0 +6
Comments 4