Features of radiation protection equipment for the staff of X-ray operating rooms

This survey is devoted to the staff radiation protection in X-ray operating rooms. For self-safety staff must regularly and correctly use the protective equipment, which is ensured by their availability, convenience and manoeuvrability during procedures performing. The rapid development of interventional radiology led to the fact that the staff work in this area have one of the highest levels of occupational exposure. Unfortunately, domestic radiation protection system does not keep pace with such a rapid development of this branch of medicine. The article shows the basic principles of the distribution of scattered radiation in the X-ray operating room during the procedures performing. The distribution of scattered radiation around the patient for various modes of C-arm angiographic systems is shown. Graphical examples of scattered radiation distribution in X-ray operating rooms are given. Collective and individual protective equipment specifically designed for staff radiation protection in X-ray operating room are considered in detail. The common data on the protection features of the recommended staff protection equipment are presented. Most of the considered protection equipment is mandatory in many European countries, but not mentioned in domestic regulatory documents yet. The proposals for the modernization of the domestic radiation protection system for staff of X-ray operating rooms have been made. These recommendations focused on providing X-ray operating rooms with relevant radiation protection equipment, including eye protection, following the accumulated world experience and international regulations.

Nonlinear Thomson scattering from a tightly focused circularly polarized laser with varied initial phases

Within the frame of classical electrodynamics, nonlinear Thomson scattering by an electron of a tightly focused circularly polarized laser has been investigated. The electron motion and spatial radiation characteristics are studied numerically when the electron is initially stationary. The numerical analysis shows that the direction of the maximum radiation power is in linear with the initial phase of the laser pulse. Furthermore, we generalize the rule to the case of arbitrary beam waist, peak amplitude and pulse width. Then the radiation distribution is studied when the electron propagates in the opposite sense with respect to the laser pulse and the linear relationship still holds true. Last we pointed out the limitation of the single electron model in this paper.

Thermal Imaging Camera Supporting the Navigation of UAVs

The topic of this paper is an evaluation of developed sensor intended for navigation aid of unmanned aerial vehicles (UAVs). Its operation is based on processing images acquired with a thermal camera operating in the long-wave infrared band (LWIR) placed underneath a vehicle’s chassis. The vehicle’s spatial displacement is determined by analyzing movement of characteristic thermal radiation points (ground, forest, buildings, etc.) in pictures acquired by the thermal camera. Magnitude and direction of displacement is obtained by processing the stream of consecutive pictures with optical-flow based algorithm in real time. Radiation distribution analysis allows to calculate camera’s self-translation vector. Advantages of measuring translation based on thermal image analysis is lack of drift effect, resistance to magnetic field variations, low susceptibility to electromagnetic interference and change in weather conditions as compared to traditional inertial navigation sensors. As opposed to visible light situational awareness sensors, it offers operation in complete darkness (harsh weather, nights and indoors).The topic of this paper is an evaluation of developed sensor intended for navigation aid of unmanned aerial vehicles (UAVs). Its operation is based on processing images acquired from a thermal camera operating in the long wave infrared band (LWIR) placed underneath a vehicle’s chassis. The vehicle’s spatial displacement is determined by analyzing movement of characteristic thermal radiation points (ground, forest, buildings, etc.) in pictures acquired by the thermal camera. Magnitude and direction of displacement is obtained by processing the stream of consecutive pictures with optical-flow based algorithm in real time. Radiation distribution analysis allows to calculate camera’s self-translation vector. Advantages of measuring translation based on thermal image analysis is lack of drift effect, resistance to magnetic field variations, low susceptibility to electromagnetic interference and change in weather conditions as compared to traditional inertial navigation sensors. As opposed to visible light situational awareness sensors, it offers operation in complete darkness (harsh weather, nights and indoors).

Influence of sunspaces on the heating demand in rooms – comparison of ISO 13790 calculation methods

The calculation method presented in ISO 13790 was developed during the research project PASSYS. It aimed to work out the way of estimating energy demand while taking into account different passive solar systems. The standard includes two calculation methods for sunspaces – a full and simplified method. They differ in terms of basic assumptions and the treatment of solar gains in the sunspace and conditioned rooms. There are some doubts about the interpretation of equations presented in the standard, especially when it comes to modelling the solar radiation distribution within the solar space. The paper presents a discussion on the basic hypotheses applied in full and simplified methods, together with the author’s suggestions regarding modifications to the ISO 13790 calculation methods. The modified methods allowed to satisfactorily predict the functioning of the exemplary sunspaces with a smaller area of glazed partitions and higher radiation absorptivity of the casing, that is spaces similar in terms of solar radiation utilisation to traditional living spaces. The phenomena typical for sunspaces with a high degree of glazing, such as the retransmission of reflected radiation, were not sufficiently taken into account in the calculation methods of the standard.

Computer Modelling of the Optical Behavior of Homogenizers in High-Flux Solar Furnaces

Solar radiation homogenizers are multi-mirror devices that try to reshape the solar radiation distribution coming from a concentrator, so that, after passing through the homogenizer, the light flux becomes as much evenly distributed as possible. The optical behavior of these multi-reflective devices is complex and still ill-understood. The geometry of the concentrator defines the features of the concentrated flux and then the characteristics of a particular homogenizer must be chosen according to the envisaged use. In this work, we developed and used optical ray-tracing software to investigate how the homogenizer’s optical output is affected by the following homogenizer’s characteristics: (i) Number of reflecting surfaces; (ii) total length; (iii) position (relative to focal plane); and (iv) tilt angle (inclination) of reflecting surfaces. The obtained results provide valuable information for the use of these optical devices and may contribute to the development of more efficient strategies for homogenization of concentrated radiation generated by high-flux solar furnaces.