Bartosz Chaber

Efficient visualization of 3D models by web browser

The article presents software module designed for efficient and convenient visualization of 3D models inside the web browser environment. It is written purely in JavaScript and takes advantages of the new HTML 5 standard. The authors focus on mobile devices, so special attention is given on efficiency and low network usage. Proposed solution based on progressive mesh streaming is compared with server side rendering approach. The results of usability tests performed on real-life random users group will be discussed.

Internet application concept to trivialize EMF biomedical computing

Purpose – The purpose of this paper is to describe a new concept of a computer system devoted to simulations of electromagnetic fields inside the human body. The main idea is based on application of the cloud computing approach to the electromagnetic simulator for inexperienced operators.Design/methodology/approach – Modular design of the system is based on web technologies. The logic of simulation processes is stored in the form of scenarios consisting of several simple steps.Findings – The authors found that a system based on a predefined, precise scenario will help an inexperienced user to solve realistic EMF simulations using state‐of‐the‐art technology. Highly modular application could be easily extended to the new functionality provided by independent programs (Processors) utilizing any type of a dedicated hardware platform.Practical implications – The remote computing is known by computer science for its early beginning, but extraordinary growth of the internet network is renewing this term for the...

A precise electromagnetic field model useful for development of microwave imaging systems

Purpose – The paper describes a fast forward electromagnetic model built with help of commercial software. The purpose of this paper is to create an efficient and robust electromagnetic field model that could be easily plugged into a working microwave imaging system. The secondary purpose is to evaluate advantages and disadvantages of such a commercial packages for creating such a model. Design/methodology/approach – In this paper the authors decided to build the model using COMSOL Multiphysics software suite, ultimately comparing its result to measurements of a real device. The numerical model was created in an iterative fashion in order to determine how much details are needed to make it reliable, while keeping it efficient. Findings – The authors found that the commercial software seems like a viable platform for developing electromagnetic solvers. The resulting computer model is easy to prepare, run and integrate with external tools. Research limitations/implications – Using the experience in building...

Morphing algorithm for building individualized 3D skeleton model from CT data

There are constant efforts to improve speed and automation of the segmentation process of CT data. We propose a semi-automatic, atlas-based method of building 3D individualized skeletons. The intervention of human operator is minimal and is limited to selection of one voxel for each bone to be segmented, measuring a few distances for a successful reconstruction and approving the final result of an alignment. As a proof of the concept, an example of creating a patient-specific model of a left femur bone is presented. The results are discussed in order to chart the route to an automatic solution. It is believed that the areas like orthopedic operation planning and patient positioning systems could benefit from our method.

Bioelectromagnetic simulation for everyone

Cloud computation technologies open a new perspective for scientific computing. Sophisticated software can now be made available as an on-demand service, reducing costs of maintenance and improving availability of the software to end-users. The paper presents a web based service system for electromagnetic computations. The back-end of the system is built of open-source scientific code. The service is targeted on medical staff and electromagnetic safety engineers which usually are not familiar with electromagnetic field simulation methods but its design allows it to be extended for more demanding, scientific-oriented users. The primary goal of the system is user friendliness for medical and engineering staff combined with flexibility, scalability and extendibility for scientists developing simulation software. These goals were achieved with help of carefully designed concept of configurable usage-scenarios (workflows). The purpose of this paper is to present in detail the concept and implementation of scientific scenarios.

Solution of the Complex-valued Helmholtz Equation using a Dedicated Finite Element Solver

This paper describes a numerical FEM model for solving the complex-valued, vector Helmholtz wave equation. The model describes phenomena of electromagnetic wave propagation for high frequencies. The presented model can be used in a larger system seeking an efficient design parameters of electromagnetic energy transfer for high power pulse generation device. Streszczenie. W niniejszym artykule opisujemy zbudowany model numeryczny MES rozwiązujący zespolone, wektorowe równanie falowe Helmholtza. Pozwala on na modelowanie zjawisk propagacji fal elektromagnetycznych wysokich częstotliwości. Zaprezentowany model może zostać wykorzystany w systemie poszukującym optymalnego projektu urządzenia służącego do przesyłu energii w postaci fali elektromagnetycznej, do generacji silnych impulsów elektromagnetycznych. (Rozwiązywanie zespolonego równania Helmholtza za pomocą dedykowanego oprogramowania MES).

Computer simulation as a way of usable volume estimation in TEM waveguides

Striplines are common waveguides used for susceptibility tests. Standards as 61000-4-20 describe procedures for finding volumes with a uniform, strong electric field, but only for frequencies below the first cut-off frequency of the stripline. For higher frequencies modes other than TEM start to propagate and an analytical determination of the field between a striplines plates is hard or even impossible (i.e. for non-homogenous interior of the stripline). The solution of electric field in a stripline could be found by means of a numerical approximation (e. g. using Finite Element Method) of Helmholtz equation. In this paper such a numerical simulation is presented. The numerical model is verified against the measurements in the frequency range above the first cut-off frequency of a stripline. On the basis of numerical simulation an electric field is determined in the stripline and a usable volume for an extended frequency range is estimated. Such a numerical simulation can be used to take into account also large metallic objects in the vicinity of the stripline.

Conformance criteria for validation of target volume surface reconstructed from delineation

This paper presents two conformance indexes that can be used to measure a similarity between two delineated structures. The authors use the presented conformance indexes for rating the results of Poisson Surface Reconstruction algorithm on real patient datasets. The rating is based on three delineations: original contours created during a standard procedure, reconstructed contours and reference contours created with an extra care by another physician.The chosen conformance indexes compare the delineations in two different forms: as a voxel grid and as a surface mesh. In this paper each of the conformance indexes is calculated in three different modes: the standard mode where all differences between datasets are taken into account and two more measuring how much one dataset exceeds the other. The last two modes are not symmetrical.The proposed conformance indexes allowed us to compare efficiently two delineations. The presented results also allow to state that the use of mesh reconstruction algorithms can improve delineations prepared within a limited time frame.

Log-periodic antenna — The comparison of different simulation models

This paper describes and compares three numerical models of small log-periodic dipole antenna, able to operate in wide band of frequencies. The experiments were performed in ANSYS HFSS, FEKO and NEC-2 simulation packages. The most important results are briefly compared.

Open access system for radiotherapy planning

The recent trends in software development transform classical desktop-based programs into distributed systems offered over the Internet. The authors adapt this approach to the radiotherapy planning software. A general concept and necessary components of such a system are presented.