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At present, the increasing number of terrorist activities has brought a focus on the problem of how to effectively maintain public order. A major challenge in this connection consists in analyzing and possibly innovating the set of existing crowd control procedures or instruments, which prominently includes non-lethal weapons (NLW) as a support tool to regulate human behavior during mass gatherings...
Steel-fiber reinforced concrete is a composite material characterized by outstanding tensile properties and resistance to the development of cracks. The concrete, however, exhibits such characteristics only on the condition that the steel fibers in the final, hardened composite have been distributed evenly. The current methods to evaluate the distribution and concentration of a fiber composite are...
The paper discusses a numerical model for more accurate analysis of electro-hydro-dynamic processes at the level of micro and nano structures. Based on previous examinations of graphene structures and using traditional modeling techniques, the authors employ diverse analyses of relevant limiting parameters to propose a structural analysis facilitating the evaluation of numerical models within the...
Polarization modulation in the near field of a coherent beam is investigated theoretically and experimentally for focusing and correcting wavefront aberrations.
The authors discuss the principle of physical similitude to obtain models suitable for the analysis and description of signal measurement tasks, whose character is evaluated quantitatively. In this context, the paper presents a simple example of using a broadband noise signal to investigate periodic structures, and it also characterizes the basic tests related to the described problem. The tested...
The aim of this paper is to present novel research in special numerical models of a coaxial line used for nanoelectronics. These models can be advantageously utilized in the evaluation of electromagnetic parameters, thus helping researchers and designers to solve problems related to nanoelectronics, sensors, and related components. The first of the models of a large periodic structure is designed...
The impact of the environment upon living organisms constitutes a crucial problem examined by today's science. Detailed examination of the overall influence of environmental factors upon humans is performed within, for example, a large number of medical disciplines. By extension, research institutes worldwide have analyzed diverse positive and negative factors affecting the biological system of the...
We present an overview of techniques for the sensing of geomagnetic field changes within the ultra-low-frequency band (1–30 Hz). Variations in the electromagnetic and chemical structure of Earth's surface can lead to altered signals in the frequency region of 6–8 Hz, which is characteristic of the alpha waves of an active brain. In the given context, diverse positive and negative factors influencing...
The authors report on an analysis of conditions on the boundary between layers having varied electromagnetic properties. The research is performed using consistent theoretical derivation of analytical formulas, and the underlying problem is considered also in view of multiple boundaries.
The authors present a survey of methods and physical principles applicable in both harvesting the energy of the infrared spectrum within broadband electromagnetic radiation and ensuring the infrared-to-visible wave conversion. Several transformation procedures are analyzed together with different approaches to fabricating resonant structures at the level of nanoparticles or nanoobjects deposited on...
The authors present a statistical evaluation of the MRI images of a plant tissue. Therefore, we compare the commonly used MRI contrast and looking for the best contrast to evaluation of MRI data of a plant tissue. The acquired images are classified in terms of the signal-to-noise ratio, intensity difference and steepness of the edges. We focused on the manual evaluation of the statistical data in...
The paper discusses the passive optical detection of small-sized targets moving through the air at overhead levels. An experimental module for a standalone locator to operate in real time is presented together with methods usable within the actual implementation of the underlying designer project. Within the supporting tests, an algorithm was developed to detect small particles in a video sequence,...
This paper will present some experiments with improving one of crucial parts of nuclear quadrupolar resonance (NQR) spectrometer, the RF decoupler. This part decouples the high power rf excitation signal from receiver port of low detected signal preamplifier. In the position of decoupler usually some LC filters and back-to-back diodes are used. We have tested rf impedance transformers of different...
Liquid crystal twisted-nematic polarization rotators in the Mauguin condition are shown to be more achromatic, less prone to high-frequency modulations caused by internal reflections than compound wave plates, and can be fabricated cost effectively at multi-inch apertures.
In order to the fiber linear birefringence compensation a promising method was chosen for pulsed current sensor design. The method employs orthogonal polarization conjugation by the back direction propagation of the light wave in the fiber. The Jones calculus analysis presents its propriety. An experimental fiber optic current sensor has been designed and realized. The advantage of the proposed method...
There are some suitable methods for the measurement of ultra-short solitary electromagnetic pulses that can be generated by high power pulsed generators. The measurement methods properties have to correspond to the fact whether we want to measure pulses of voltage, current or free-space electromagnetic wave. The need for specific measurement methods occured by the development of high power microwave...
There are certain optical methods for the measurement of ultra-short solitary electromagnetic pulses or low-level measurement. The measurement methods properties have to correspond to the fact of whether we want to measure pulses of voltage, current or a free-space electromagnetic wave. The need for specific measurement methods occurred owing to the development of high power microwave pulse generator...
The article deals with results which were obtained during the design of LVDS (low voltage differential signaling) bus. This bus is very resistant to interference from the environment and to spurious emission of electromagnetic fields. According to requirements we prepared designs of LVDS by means of numerical methods. The design was realized and its parameters verified experimentally. The basic parameter...
There are some suitable methods for the measurement of ultrashort solitary electromagnetic pulses (EMP) that are generated by high-power microwave generators. The characteristics of EMPs are high-power level (Pmax = 250 MW) and very short-time duration (tp euro (1, 60) ns). Special requirements for measurement methods have to be considered because of the specific EMPs properties. In this paper, two...
In connection with the events of the last few years and with the increased number of terrorist activities, the problem of identification and measurement of electromagnetic weapons or other systems impact occurred. Among these are also microwave sources, which can reach extensive peak power of up to Pmax = 250 MW. Solitary, in some cases several times repeated, impulses lasting from tp epsi <1,...
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