Devices and Methods of Measurements (E-Journal) / Приборы и методы измерений
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ПРИМЕНЕНИЕ МНОГОПАРАМЕТРИЧЕСКОГО АНАЛИЗА ШИРОКОПОЛОСНЫХ СПЕКТРОВ ПРОПУСКАНИЯ ДЛЯ ИДЕНТИФИКАЦИИ ВИН С ГЕОГРАФИЧЕСКИМ НАИМЕНОВАНИЕМ ПРОИСХОЖДЕНИЯ
Get PDFThe simulation is carried out of physical and chemical characteristics of the unblended varietal young Moldovan wine harvested in 2014 by the projection to latent structures of the transmission spectra in the range of 220–2500 nm. The achieved accuracy of the regression determining the parameters is appropriate for practical application purposes (from 5 % for alcohol strength to 30 % for tartaric acid content in red wines). The possibility is shown of solving the problem of verification of the protected geographical indication of wines (IGP – Indication Géographique Protégée) by the multivariate analysis of broadband transmission spectra. Проведено моделирование физико-химических характеристик молодых некупажированных сортовых молдавских вин урожая 2014 г. с помощью проекции на латентные структуры спектров пропускания в диапазоне 220–2500 нм. Достигнутая погрешность регрессионного определения параметров является приемлемой для целей практического применения (от 5 % для спиртуозности до 30 % для содержания винной кислоты в красных винах). Показана возможность решения задачи подтверждения общности географического наименования вин (IGP – Indication Géographique Protégée) с помощью проведения многопараметрического анализа широкополосных спектров пропускания
СКЛЕРОМЕТРИЧЕСКИЙ МЕТОД ИЗМЕРЕНИЯ МИКРОТВЕРДОСТИ ПЛЕНОК ФОТОРЕЗИСТА НА КРЕМНИИ
Get PDFIn recent years new types of resist for nano and submicronic lithography are intensively developed. As perspective materials for resist various polymeric compositions on a basis thermally and mechanically resistant polymers are considered. The purpose of the real work was studying of possibility of application of a microindentation and scratching methods for research of strength properties of films of the polymeric resist applied on plates of single-crystal silicon. As an example films of positive diazoquinonenovolak photoresist 1,0–5,0 μm thick which were applied on plates of silicon of various brands with a centrifugation method were used. The comparative analysis of an microindentation and scratching methods for microhardness measurement of structures photoresist-silicon is carried out. It is shown that the scratching an edge of a tetrahedral diamond pyramid (a scratching method) is suitable for microhardness measurement of resistive films from 1,0 μm thick, at the same time the method of an microindentation can’t be used for measurements thin (h = 1,0–2,5 μm) photoresist films. When using the load P = 1–2 g, more accurate values of microhardness gives the scratching method. Value of the microhardness determined by a scratching method is 20–40 % more than value of the microhardness received by a microindentation method. The increase in loading to 10 g leads to leveling of the specified distinctions – the values of a microhardness received by both methods coincide. Radiation of resistive films changed the structure of resist films. It is results to correlation of microhardness values given on measurement as by a scratching method, and by an indentation method.
ВЛИЯНИЕ ДЕТАЛЕЙ ИЗ УГЛЕПЛАСТИКА НА СВЕТОРАССЕЯНИЕ В ОБЪЕКТИВЕ ОПТИКО-ЭЛЕКТРОННОГО МОДУЛЯ КОСМИЧЕСКОГО АППАРАТА
Get PDFSpacecraft optoelectronic modules traditionally have aluminum alloy or titanium alloy casing which substantial weight increases fuel consumption required to put them into orbit and, consequently, total cost of the project. Carbon fiber reinforced polymer based composite constructive materials is an efficient solution that allows reducing weight and dimensions of large optoelectronic modules 1,5–3 times and the coefficient of linear thermal expansion 15–20 times if compared with metals. Optical characteristic is a crucial feature of carbon-fibre-reinforced polymer that determines composite material interaction with electromagnetic emission within the optical range. This work was intended to develop a method to evaluate Carbon fiber reinforced polymer optoelectronic modules casing effect on lens scattering by computer simulation with Zemax application software package. Degrees of scattered, reflected and absorbed radiant flux effect on imaging quality are described here. The work included experimental study in order to determine bidirectional reflectance distribution function by goniometric method for LUP-0.1 carbon fabric check test pieces of EDT-69U epoxy binder with EPOFLEX-0.4 glue layer and 5056-3.5-23-A aluminium honeycomb filler. The scattered emission was registered within a hemisphere above the check test piece surface. Optical detection direction was determined with zenith (0º < θ < 90º) and azimuth (0º < φ < 180º) angles with 10° increment. The check test piece surface was proved to scatter emission within a narrow angle range (approximately 20°) with clear directivity. Carbon fiber reinforced polymers was found to feature integrated reflectance coefficient 3 to 4 times greater than special coatings do.
ВЫСОКОЭФФЕКТИВНЫЙ ПРИЕМНИК ИНФРАКРАСНОГО ИЗЛУЧЕНИЯ
Get PDFRecent research and development show promising use of high-performance solid-state receivers of the electromagnetic radiation. These receivers are based on the low-barrier Schottky diodes. The approach to the design of the receivers on the basis of delta-doped low-barrier Schottky diodes with beam leads without bias is especially actively developing because for uncooled receivers of the microwave radiation these diodes have virtually no competition. The purpose of this work is to improve the main parameters and characteristics that determine the practical relevance of the receivers of mid-infrared electromagnetic radiation at the operating room temperature by modifying the electrodes configuration of the diode and optimizing the distance between them. Proposed original design solution of the integrated receiver of mid-infrared radiation on the basis of the low-barrier Schottky diodes with beam leads allows to effectively adjust its main parameters and characteristics. Simulation of the electromagnetic characteristics of the proposed receiver by using the software package HFSS with the basic algorithm of a finite element method which implemented to calculate the behavior of electromagnetic fields on an arbitrary geometry with a predetermined material properties have shown that when the inner parts of the electrodes of the low-barrier Schottky diode is performed in the concentric elliptical convex-concave shape, it can be reduce the reflection losses to -57.75 dB and the standing wave ratio to 1.003 while increasing the directivity up to 23 at a wavelength of 6.09 μm. At this time, the rounded radii of the inner parts of the anode and cathode electrodes are equal 212 nm and 318 nm respectively and the gap setting between them is 106 nm. These parameters will improve the efficiency of the developed infrared optical-promising and electronic equipment for various purposes intended for work in the mid-infrared wavelength range.
ЭКСПЕРИМЕНТАЛЬНОЕ УСТРОЙСТВО ДЛЯ МОДЕЛИРОВАНИЯ И ИССЛЕДОВАНИЯ СЛОЖНОГО НАПРЯЖЕННОГО СОСТОЯНИЯ В ФЕРРОМАГНИТНЫХ МАТЕРИАЛАХ
Get PDFПРОГРАММНО-АППАРАТНЫЙ КОМПЛЕКС ДЛЯ ИССЛЕДОВАНИЯ ПРОЦЕССОВ ТРЕНИЯ И ИЗНОСА МЕТОДОМ «ДИСК НА ПЛОСКОСТИ»
Get PDFИСПОЛЬЗОВАНИЕ ПРИЗМЕННОГО ТЕЛЕСКОПИРОВАНИЯ СВЕТОВОГО ПУЧКА ДЛЯ ПОВЫШЕНИЯ СПЕКТРАЛЬНОГО РАЗРЕШЕНИЯ И УГЛОВОЙ ДИСПЕРСИИ СПЕКТРОМЕТРА
Get PDFThe increase of angular dispersion and slit resolution limit of grating spectrometers by means of variation of grating parameters is limited by its period and allowable order of diffraction. The special solutions (echelle, holographic, immersion gratings) are acceptable in a limited parameter range and are technologically complex in fabrication, thus hardly applicable to instruments of mass production. We propose to decrease slit resolution limit by one-dimensional beam widening in dispersion plane by means of passing it through oblique prism before incidence onto diffraction grating. The increase of angular dispersion can be achieved by narrowing of dispersed beams after grating while passing through other oblique prism. We prove that slit resolution limit in such a system changes approximately as multiplied by angular magnification of the first prism (that is less than 1 times). Also angular dispersion changed approximately as multiplied by angular magnification of the second prism. The Fresnel reflection from the faces of prisms is analyzed. Accounting for that factor gives the increase of resolution about 1,4–1,6 times without loss of light (and can be 2 and more times while using anti-reflective coating). The proposed method is different from the similar ones first of all by its simplicity because it uses simple optical elements – plane reflective grating and thin prisms. It can be applied to amend the analytical characteristics of dispersive spectrometers, first of all the small-sized ones.
ИСПОЛЬЗОВАНИЕ СПЕКТРАЛЬНОГО АНАЛИЗА МЕТОДОМ БЕРГА ПРИ ПОСТРОЕНИИ ПРОГРАММНО-МАТЕМАТИЧЕСКОГО ОБЕСПЕЧЕНИЯ ОПТИЧЕСКИХ СИСТЕМ ВИБРОДИАГНОСТИКИ
Get PDFThe objective of this paper is development and experimental verification special software of spectral analysis. Spectral analysis use of controlled vibrations objects. Spectral analysis of vibration based on use maximum-entropy autoregressive method of spectral analysis by the Berg algorithm. For measured signals use preliminary analysis based on regression analysis. This analysis of the signal enables to eliminate uninformative parameters such as – the noise and the trend. For preliminary analysis developed special software tools. Non-contact measurement of mechanical vibrations parameters rotating diffusely-reflecting surfaces used in circumstances where the use of contact sensors difficult or impossible for a number of reasons, including lack of access to the object, the small size of the controlled area controlled portion has a high temperature or is affected by strong electromagnetic fields. For control use offered laser measuring system. This measuring system overcomes the shortcomings interference or Doppler optical measuring systems. Such as measure the large amplitude and inharmonious vibration. On the basis of the proposed methods developed special software tools for use measuring laser system. LabVIEW using for developed special software. Experimental research of the proposed method of vibration signals processing is checked in the analysis of the diagnostic information obtained by measuring the vibration system grinding diamond wheel cold solid tungsten-containing alloy TK8. A result of work special software tools was complex spectrum obtained «purified» from non-informative parameters. Spectrum of the signal corresponding to the vibration process observed object.
ИДЕНТИФИКАЦИЯ ДИНАМИЧЕСКИХ ХАРАКТЕРИСТИК АВИАЦИОННЫХ ДАТЧИКОВ ТЕМПЕРАТУРЫ ГАЗОВ
Get PDFThe estimation of dynamic behavior of aircraft gas temperature sensors (GTS) has to be done only in certified air installations and be based on recorded experimental transient response in accordance with the departmental standard. Experimental transient response has hindrances of different nature and can influence the accuracy of identification of dynamic behaviour of GTS. We suggested a new method to increase the accuracy of identification of dynamic behavior of GTS. The method is based on the use of amplitude spectrum of signal composed of experimental transient response. Shaped signal is an impulse decaying signal satisfying a Dirichlet condition and Fourier transform can apply to it to get amplitude spectrum. We worked out the relation between amplitude spectrum of shaped signals and time constant of dynamic behaviour for three mathematical models of GTS. The research showed that the information about dynamic behaviour of standard aircraft GTS is located in LF part of amplitude spectrum in the range of 0 to 1 rad/s and to 3 rad/s. The study revealed that hindrance in the transient response at frequency higher than 3 rad/s did not influence the accuracy of results if to use LF part of amplitude spectrum for the identification of dynamic behaviour of GTS. The amplitude spectrum of shaped signal can be estimated by measuring equipment like LF spectrum analyzer or calculated by software package with the function of fast Fourier transform. The value of time constant of certain mathematical model of GTS can be realized with the help of regression analysis or the use of embedded resources of different data processing systems. Thus, the method gives an opportunity to increase the accuracy of identification of dynamic behavior of GTS.