Mathematical model of the fuel element of the nuclear reactor

Mathematical model of the fuel element of the nuclear reactor  
The fuel element (TVEL) is the main structural element of the core of a heterogeneous nuclear reactor containing nuclear fuel[1].
In TVELs fission of heavy nuclei of uranium 235 or plutonium 239 occurs, accompanied by the release of thermal energy, which is then transferred to the heat carrier.
TVEL should ensure the removal of heat from the fuel to the heat carrier and prevent the spread of radioactive products from the fuel to the coolant.
Therefore, the calculation of the temperature fields in fuel elements is an important task of designing a nuclear reactor.

R means regression

Statistics recently received a powerful PR support from more new and noisy disciplines -
Machine Learning
Big Data
. Those who seek to saddle this wave will be friends with
regression equations
. It is advisable to not only learn 2-3 examiners and pass the exam, but also be able to solve problems from everyday life: find the relationship between the variables, and ideally - be able to distinguish the signal from noise.
R means regression
For this purpose, we will use the programming language and development environment
, which can not be better adapted to such problems. At the same time, let's check what the rating ...

Binary-ternary bit magic

There is a classical problem for interviews, often formulated as follows:
There is an array of natural numbers. Each of the numbers is present in the array exactly twice, and only one of the numbers does not have a pair. It is necessary to propose an algorithm that, for the minimum number of passes through the array, determines a number that does not have a pair.
I suppose no one will be offended if I immediately bring up the solution of the problem: the unique element will coincide with
Binary-ternary bit magic
-sum of all elements of the array, calculated in linear time.
I propose to think about another variation of this problem...

Suspended fuel tanks for airplanes

Suspended fuel tanks for airplanes  
Often, to ensure a long flight range, additional tanks are hung from the outside on the outside. Suspended tanks can be dropped and not dropped.
Dropped pendant tanks after the consumption of fuel from them are dumped in the same way as aerial bombs from the lock of the bomb holders, to which they are suspended.
Power from the suspension tanks is carried out by including pipelines from these tanks in the common system of supplying the engine with fuel through a stop or multi-way valve.
An interesting fact is that in the Vietnamese jungle after the war began to find a ...

Basics of sorting for beginners and examples of basic variants

Probably every programmer, whether it's a backend, whether it's a frontend, whether it's a game developer, everyone once had to sort something. And mostly pretty often.
In this article, most standard sorting algorithms will be described, their differences and what is the time complexity of the algorithm (in the word "temporary" letter a).
Basics of sorting for beginners and examples of basic variants complexity
By th...

The game with ormatas

I suggest you play the game. I give you a square grid on which some cells are painted over, and some may remain empty. We will call it a "template". For example, a grid can be one of these templates:
The game with ormatas
You have a stack of transparent plastic sheets, in size and shape matching the mesh, on which the patterns from the black dots are painted:

It is worth noting that in each of these patterns exactly three points, one point in each row and column. The six combinations shown are the only 3 × 3 meshes that have this property.
Your task is to collect a subset of transparent sheets and apply them to the template so that the points close all the filled squares, but do not fall into any of the empty ones. You can apply several points to any of the filled ...

"Tutor: mathematics" to prepare for the exam and VPR - from the idea to the release. Story about the unique educational project

A mathematical package for Android "Micro Mathematics": what's new?

A mathematical package for Android "Micro Mathematics": what's new? That flew six months since I was translated his mathematical package to Android , "Micro-Mathematics", into the status of free open source applications and published the code at github . Thanks to this step, "Micro-Mathematics" received a powerful impulse for development, and I myself - a valuable and very positive experience with the community. In this short note, I want to present a new version of the application that is currently preparing for release, as well as share all the positive things that were received in the framework of the release. This note is for those who are interested in both ...

Analysis of the consensus algorithm in Tendermint

Analysis of the consensus algorithm in Tendermint
This article describes the BCA (Byzantine Consensus Algorithm) algorithm used in Tendermint. Developed on the basis of the DLS protocol, it does not require any "active" mining, as in Proof-of-Work, and can ensure the safe operation of the network with at least 2/3 + (strictly more than two thirds) of "honest" network members. Below is a story about how this algorithm is implemented in Tendermint, the statistics of its operation are given and the behavior of the algorithm is simulated on a small network of five participants.
NEM with Proof-of-Importance and ...

A futuristic method for calculating the settings of regulators using Python

A futuristic method for calculating the settings of regulators using Python  


The non-search method is a simple, reliable and universal method for calculating the settings of suboptimal controllers, including algorithms such as PD, PDD and PIDD[1].
However, given in[1]the software implementation of this method has a number of drawbacks, which makes it difficult to use in microprocessor control devices.
Among the shortcomings can be identified as:
Ambiguity in determining the range of operating frequencies, which, even if there is a smoothing link in the structure of the transfer function of the regulator, can lead to negative settings;
In the paper[1]for ...[/h]