Криміналістична техніка та методика
Permanent URI for this collection
Browse
Recent Submissions
Item Дальність дії тепловізора та чинники, які на неї впливають. ACTION RADIUS OF THERMAL IMAGER AND FACTORS AFFECTING IT(2018) Неня, О.В.; Nenia, O.V.Several technical and optical factors, observation conditions that affect the range (detection distance of thermal radiation) of thermal grids, including military ones, which are simultaneously the main criteria for their selection, are considered. Such concepts as “detection range”, “recognition,” and “identification,” characterizing different degrees of the vision of the target (object) with a thermal imager, are highlighted. Attention is drawn to a probabilistic index – the Johnson criterion, which, although it is probabilistic, since it depends on a number of random factors, is however the most universal and widespread one. It gives a forecast of the efficiency of the thermal imaging camera for solving a specific problem in certain conditions. Among the important factors affecting the range of action of thermal imagers, the thermal transparency of the atmosphere is considered. Since thermal radiation weakens due to the absorption of gas by molecules, dust, aerosols, etc., an important component of the effective operation of thermal imagers is the so-called “transparency win- dows” – spectral ranges convenient for their work. Among the technical factors that significantly affect the range of the thermal imager, paper details the resolution of its photodetector (or matrix), the dimensions of which (the number of sensitive elements (pixels) located horizontally and vertically) determine the final image clarity. An important parameter that significantly affects the range of a thermal imager is the focal length of the objective lens (lens) of the thermal imager, collects and focuses IR radiation on the matrix in accordance with the temperature distribution of the observed object. The radius of action of the thermal imager depends on the focal length of the lens, which also affects the so- called instantaneous sector of the system overview (IFoV) – the angular resolution of the system. The value of the focal length and angular resolution are inversely proportional, which is enshrined in the paper by mathematical calculations. Speaking about the focal length of the lens, we should not forget about the sharpness of the displayed space, which depends on the lens aperture, and which characterizes the degree of attenuation by the lens (lens system) of the infrared imager from the object of observation. Paper concluded that determining the range of the thermal imager, as a function of multiple variables, requires a fairly complex simulation.Item Сучасні криміналістичні засоби виявлення потожирових слідів рук людини. MODERN CRIMINALISTIC MEANS OF IDENTIFICATION OF THE LONG-TERM HUMAN BEARINGS(2018) Грусевич, В.О.; Hrusevych, V.O.Paper is devoted to the study of modern forensic means of detecting traces of human hands on various surfaces in laboratory and extra-ballast conditions. In particular, the focus is on reviewing and analyzing the latest forensic developments, such as alloxan, DFO, ruthenium tetroxide, as well as the products of Sirchie company, which does not contain any foreign DNA. Peculiar features of individual means of detecting finger-prints are highlighted by positive qualities and disadvantages. It is noted that the use in forensic practice of reagents, alloxan and DFO significantly simplifies the process of detecting the finger-prints, since it is a one-stage treatment, which does not require further treatment with metal salts of bivalent metals. On the basis of the study of the stages of the mechanism of practical application of ruthenium tetroxide, it is noted that the process of detecting finger-prints should be carried out in well-ventilated rooms, either under traction or in special closed cells (glass vessels), since the used solution is a weak irritant. It is noted that the advantage of the method of detecting latent finger-prints using tetraoxide ruthenium in its sufficient versatility, ease and speed of detecting latent traces on objects-tracers without pre- training, as well as the possibility of further by use other excellent detection methods. The method also allows the detection of traces on such complex surfaces as heat- sensitive paper, human skin, and a sticky layer of adhesive tapes. According to the results of the analysis of fingerprint powders from Sirchie, it is emphasized that they have a fine-dispersed structure, thereby providing a good sticking to the substance of the tired substance and as a result of the excellent quality of fingerprints of the human hands. This powder can be used on porous, and non-porous surfaces, such as: colored wood, metal, most plastic coatings. According to the results of the research, a number of author’s conclusions, suggestions and generalizations have been suggested.