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$15 USD / hour
dnipro, ukraine
$15 USD / hour
It's currently 5:58 AM here
Joined September 10, 2015
0 Recommendations



4.9 (2 reviews)
$15 USD / hour
dnipro, ukraine
$15 USD / hour
Jobs Completed
On Budget
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Repeat Hire Rate

Scientific software, web and mobile development

We are a Ukrainian software development company that employs several passionate engineers. Our main focus is scientific software, but we also do web and mobile development. In the last few years we have completed many complex projects for our customers that cover the areas of health care, IoT, ML (computer vision and natural language processing), AR/VR, CAD/CAE, video production equipment, simulation in neuroscience, financial markets, HPC and more. We develop desktop apps, back end, front end (including design), mobile (including cross-platform) and firmware. QA and test coverage are provided as well as post-release support. Our developers are trained on internal projects that are presented on our website. They have diversified skill sets that cover the most popular frameworks, tools and languages. Our team can carry out your project independently or integrate into your existing development team. We would be happy to take care of your boldest and most complicated projects!
Freelancer Java Developers Ukraine

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Portfolio Items

In this project, we developed a website and two mobile apps (for Android and iOS) that let you see weather forecast for Ukrainian territory. The website and the mobile clients share the same backend.
The backend has microservice-based architecture and consists of four modules: Processor, Collector and two Web modules, on server side and UI module on client side. The application collects weather data from external services, shows it on the map of Ukraine graphically and also in the weather table textually.
The Android app was created in Kotlin with the new architecture components recommended by Google on Google I/O 2018. We used Android Jetpack being a collection of Android software components such as AndroidX, Lifecycles, LiveData, Room, ViewModel, WorkManager, Preferences and much more.
The iOS app was created in Swift with the last architecture components that Apple recommended. We used Storyboard in collaboration with Auto Layout.
Ukraine Weather Map
This project was devoted to fluid mechanics modeling with OpenFOAM library being an extremely powerful open source toolbox with a broad set of solvers mainly designed for computational fluid dynamics.
Both preparation of the input data and visualization of the output data are nontrivial for this library, requiring some expertise in working with it. The application we developed facilitates the interface between end user and OpenFOAM making it easy to formulate a problem, conduct simulation and analyze its results. With a friendly GUI, the user can adjust spatial and temporal grids, set initial distribution of fluid in tank and start the finite-difference time-domain process with just one mouse click. The results of simulation are automatically loaded, postprocessed and shown to the user in the form of an animation. Optionally, they can be saved to a video file with AVI extension.
A video sample can be found here:
Fluid Mechanics
The goal of this project was the implementation of a full analogue of iirlpnorm Matlab function being a part of DSP System Toolbox. The function is for the synthesis of Infinite Impulse Response (IIR) digital filter with piecewise-linear amplitude response using least-weighted-Pth approximation. It is not an open-source function in contrast to many other Matlab functions. A quasi-Newton minimizer in couple with a simplex line searcher are employed in the heart of our program. Since the objective function is very jagged, it was decided to use a two-stage optimization strategy with two objective functions minimized in sequence. The first objective function being a rough approximation of the second (true) objective function has a virtue of smoothness. It allows us to obtain a good initial estimate for the second stage of optimization. The program was implemented in C++ with the usage of Intel® Math Kernel Library for polynomial roots finding. See:
IIR Filter Design
In this project, we modeled the Solar system based on real celestial mechanics. A system of ordinary differential equations is solved numerically with the actual positions and velocities of space bodies taken as the initial conditions. This application provides flexible control of the camera to observe the Sun, planets and satellites from different points, allowing you to watch this amazing physical process that is otherwise inaccessible to the human eye. It is possible to switch the observer’s location between space bodies and see, for example, a sunrise on Mars. The standard 3D camera operations like rotation, panning, zooming etc. are supported. The Sun and the planets are very small in comparison with the distances between them. This is why we provided a panorama mode in this application so that the user can watch the bodies in a much bigger size and closer to each other than they are in real life. A video sample can be found here:
Solar System
The methods of piecewise constant and piecewise linear approximation of complicated inhomogeneous layers are investigated. The expressions for transmission matrices for linearly inhomogeneous and exponentially inhomogeneous layers have been obtained. The accurate and approximate values of reflection coefficient against frequency for the exponential and linear matching layers have been obtained. Piecewise constant and piecewise linear approximation methods have been compared according the criteria of calculation time consumption and accuracy of the result. The piecewise linear approximation method is more suitable in the case when the permittivity is a rapidly varying nonmonotonic function.
Calculation of Reflection Coefficient of Complicated Layers
Bragg structures with nonlinear lumped elements and layers with Kerr nonlinearity are considered. The pseudoinverse method for calculation the field at boundaries of the structures has been proposed. This method is the combination of the transmission matrix method and the Jacobi iterative procedure. This approximate numerical method takes into account changing the field amplitude on the thickness of the nonlinear layer. The sufficient accuracy of proposed method can be achieved by increasing the number of sublayers under decomposition of the nonlinear resonance layers. The presence of several nonlinearities in the resonant layer of Bragg resonator leads to a complex hysteretic behavior of the frequency characteristics due to the redistribution of the field between the parts of the resonance layer with different (decreasing and increasing) nonlinearity. The characteristics of layered structure strongly depend on the location of the nonlinear lumped element inclusion.
Resonance in Layered Bragg Structures with Nonlinear Element


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$4,033.26 USD
We've been very pleased with the work that UnboltSoft has done for us and look forward to working with them again when the need arises.
Java SQL NoSQL Couch & Mongo English (US) Translator Backend Development
Flag of Matthew A. @MatthewAry
4 years ago
$880.00 CAD
all good thx.
Python Software Architecture MySQL C++ Programming R Programming Language
Flag of Linda Sue J. @hidhurst1
6 years ago

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Java 1 Python 1 SQL 1 NoSQL Couch & Mongo 1 MySQL 1

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