The work is devoted to the creation of a side backlight system for liquid crystal displays that allows for the implementation of dynamic contrast. The work proposes to use a "light-guiding layer-nematic liquid crystal" structure instead of a transparent light-guiding plate, which allows for the control of the backlight intensity of individual display sections by changing the applied electric field. The work contains modeling of light transmission through the proposed structure and the results of experimental studies. The proposed method allows for the first time to implement dynamic contrast in liquid crystal displays with side backlighting.

The work is devoted to the development of a method for assessing the perfection of nematic liquid crystal structures based on determining the contrast of individual sections of conoscopic images. The results of studies of the influence of the external electric field and vibration on planar nematic structures are presented, the optimal values of the control voltage and the maximum permissible values of vibration are found.

The work proposes the use of a unique method of creating passive, multifunctional, non-contact pressure-temperature sensors. The basis of this method is a combination of inorganic semiconductors and high-molecular organic cholesteric crystals. According to their morphology, such crystals represent a spiral structure that is sensitive to changes in external physical factors, such as temperatures, due to changes in the periodicity of the structure, which leads to Bragg diffraction scattering of light on it. The consequence of such influence is the coloring of the cholesteric, which can be identified by external spectrosensitive devices on a non-contact basis. On the other hand, the use of inorganic semiconductors involves the production of a micro-profiled base with a thin silicon membrane that is sensitive to external pressure. The thickness of the membrane determines the operating conditions of the sensor depending on the range of applied pressure from 0.3 bar and above. A hardware and software complex was developed for continuous monitoring of changes in the color of passive pressure-temperature sensors, tracking the spectral distribution of the light intensity of the color of the liquid crystal depending on the operating conditions on a non-contact basis with an external spectrometer. The basis of such a system is a software module created on the basis of the MVVM (Model–View–View Model) architecture template. A feature of the software module is the use of the .NET and WPF frameworks, which natively support this architectural pattern for .NET Windows platforms and are supported by all popular versions of operating systems. The SQlite database, which is a relational database management system, is used to store data in the software application. The OmniDriver library was used in the system to operate and configure the spectrometer. The software module has two modes of operation with spectrometers. The first mode is characterized by the reading of a single spectrum, while the second mode is characterized by periodic reading and processing of the intensity spectral distribution in real time with a given period. When using the second mode, the software module allows you to dynamically change the periods and parameters of changing the color parameters of the light over time. The main algorithm of the software module is the transformation of the spectral intensity distribution normalized in the CIE XYZ color model, which is the basis for all further calculations, into the RGB model.

In the work, a study of the design and technological direction of creating a dual-functional non-contact pressure and temperature sensor based on silicon-cholesteric crystal systems was carried out. An optically active environment based on a supramolecular spiral structure is a sensitive element for forming the optical response of a microelectronic label sensor during non-contact monitoring of the state of a physical object using a spectrometer. The optical response of the device provides maximum intensity in the case of interference that corresponds to the Wulff–Bragg condition. The functionality of the sensor is ensured by the conditions for avoiding high electromagnetic interference during optical identification. A hardware and software modules have been created for non-contact monitoring of the state of physical objects, the main part of which is graphical user interface that corresponds to the MVVM architectural design pattern. Visualization of the spectral intensity using the software module was provided by conversion to the RGB model. The algorithm of procedure for calculating the color rendering index is given. In a wide range of light waves, the main parameters' color temperature was defined.

This article presents a case study detailing the application of Change Data Capture (CDC) technology for migrating from a monolithic architecture to a event-driven microservices. The article outlines the proposed architectural approach, emphasizing its benefits and addressing the challenges encountered during implementation. Key highlights include the strategic utilization of CDC and a message broker to enable seamless data replication and event-driven communication among microservices. The study delves into the incremental migration strategies. Additionally, the article discusses the impact of this migration on system performance, offering insights from performance experiments conducted to quantify results. The culmination of these efforts underscores the significance of a well-considered migration strategy and provides valuable insights for organizations considering a similar architectural transition.

Because of the rapid development of new types of light sources and price considerations, effective methods to analyze the characteristics and quality of light sources are required. To solve the problem of certification and standardization of light sources, and continuing of the further research, an automated system was developed that analyzes light characteristics based on input data and calculates the quality mark of the light source based on the obtained results. We have developed two versions of the system. The main version is based on the spectral distribution obtained from the spectrometer and provides a precise instrument for research and certification of light sources. The second one is a mobile version that uses a device camera for getting the light data and allows to evaluate the household light sources. In this paper, we present the description of the developed system and the main methods of light analysis that we implemented.

The contrast characteristics of cholesteric-nematic transition (CNT) in nematic-cholestric mixtures with a low (up to 2weight %) optical active dopant content were analysed.

Проаналізовано існуючі системи розпізнавання людей та дано їх характеристику. Окремо описано особливості двоступеневого та одноступеневого розпізнавання образів, наведено методики підвищення продуктивності глибоких нейронних мереж за допомогою зменшення кількості операцій. Подано особливості роботи нейронних мереж на основі YOLOv3 та охарактеризовано архітектуру досліджуваного алгоритму. Описано програмну реалізацію для YOLOv3 з участю фремворка Darknet та бібліотеки Tensorflow. Описано процес тренування досліджуваної нейтронної мережі. Отримані результати навчання свідчать, що покращена мережа має хорошу продуктивність в задачах розпізнавання і класифікації цілей.

Given the pandemic situation around the world, mental and physical wellbeing become a crucial part of our lives, having said that health support is one of the most popular topics nowadays. In order to keep mental stability, we have to feel when the actual help is needed. Sometimes it’s extremely hard to analyze our mental and physical health and the time when we need to ask for help. In this work, we built the module for mental illness classification, which can identify mental states based on human text input. The module is part of a platform for physical and mental state identification based on user journaling. The platform will allow daily journaling and automatically identify user mental and physical states based on the texts.

The development of efficient organic light emitting diodes (OLED) based on the phenomenon of intramolecular thermally activated delayed fluorescence (TADF), in the design of which there are no blue phosphorescent emitters based on rare earth metals, still remains a challenge in the development of new lighting systems and OLED displays. The article proposes a technological approach to the formation of new type of OLED, where the emitter is an organic donor-acceptor molecular material 9- (2,3,5,6-tetrachloropyridin-4-yl) -9H-carbazole (4-CzPyCl4), in which electronic interaction between the donor and acceptor fragment plays a key role in the mechanism of delayed fluorescence. The design of the developed light-emitting heterostructure uses layer-by-layer formation of functional nanosized organic films, in contrast to traditional OLED designs of dark blue color radiation, which uses a guest-host systemThe external quantum efficiency of the developed OLED is 2.8%. The maximum brightness of 3,000 cd/m2 is reached at a voltage of 15 V. The chromaticity coordinates CIE (x, y) 1931 are (0.15, 0.13), which corresponds to the “dark blue” emitting spectral zone.

The paper shows the possibility of using convolutional neural networks to solve the problem of diagnosing pathologies of the thyroid gland. The proposed system consists of two main parts: an online service for data collection and a decision support system for the classification of thyroid nodules. The online service for data collection is implemented in the form of a web application, which accumulates the results of ultrasound investigation of the thyroid gland, both in numerical and graphical form and the results of fine-needle aspiration biopsy (FNA).

The paper is devoted to the initial stages of the developing of a system for computer monitoring of environmental physical and chemical parameters using computer vision systems. The way of using specially designed QR codes as optical identifiers for a set of sensors along with the white standard is shown. A number of materials have been considered for use as an optically active sensor environment for such monitoring system.

A retrospective study of the results of the examination of 160 patients who underwent fineneedle aspiration biopsy of thyroid nodules has been conducted. Possibilities of using the TIRADS (Thyroid Imaging Reporting and Data System) scale as a standardized USG thyroid examination protocol have been considered. Combinations of indicators (sex, age, ultrasound characteristics) were analyzed with the help of multifactor regression in order to recommend the thyroid fine-needle aspiration biopsy. Measures to increase the ultrasound database, which will allow further use of neural networks for their analysis, have been developed.

This article shows the results of computer simulation of lens with variable focus. The basis of the lenses is a polymer with a complex surface (in this case - Fresnel zones) covered with a thin layer of liquid crystal.

The results of studies of the electrically controlled elements of optical systems based on hydrogel - electrochromic polymer with conjugated pi-electron system are shown. One important feature of conjugated polymers is the ability to change their optical characteristics under an external electric field. The electrochromic effect of these polymers may find applications in optical gating and filtering systems, optical sensors, smart windows'', optical memories, IR-switching, and electrochromic displays. Such electrochromic polymers were embedded in the matrix of a macroporous polymer hydrogel by the oxidative chemical polymerization method. The obtained samples based on hydrogel - polyaniline and hydrogel - polyorthotoluidine composites demonstrate the electrochromic behavior. In these composites, the electrolyte, as well as the electrochromic polymer, are located directly in the volume of hydrogel.

The work is devoted to the creation of OLED structures, as a light source for optical temperature sensors, and to the study of their optical characteristics. We have carried out the modeling of light-emitting structures in order to select the materials of layers and a technology for their production based on the necessity of obtaining the appropriate spectral characteristics. The optical characteristics of OLEDs and OLED-LC structures are also studied.

The concept of constructing functionally integrated sensors of thermal quantities is formulated on the basis of calorimetric methods of investigation, the novelty of which is the usage of components of solid-state microelectronics and multifunctional signal converters. The analysis and selection of organic materials has been carried out, and the green colored OLED has been formed with good output characteristics for temperature sensors. The spectral analysis of proposed structures is represented and the method of their obtaining is selected.

The investigations of system based on cholesteric liquid crystal (CLC) sensors of physical quantities with an information transfer optical channel are carried out in the paper. The results of experimental investigations of spectral characteristics of polymer dispersed cholesteric liquid crystals (PDCLC) are represented. The application such material as primary transducer of a temperature sensor is proposed. The structure of an optical fiber temperature sensor with successive allocations of primary transducers and shifted areas of selective reflection band has been designed.

The work is dedicated to computer simulation of optical properties and dynamic characteristics of polymer dispersed cholesteric liquid crystals for their application as optically active medium in optoelectronic systems. The influence of the physical parameters of the individual elements of the structure on processes of light passing and temperature distribution is analyzed.

In paper as the gas sensitive material of primary transducer of SO2 and NO2 optoelectronic multi-sensor the 5CB nematic liquid crystal (NLC) are used. The sensitivity of our sensitive element by means of adding to 5CB the cholesteric liquid crystal (CLC) was increased. The electrical realization of our multi-sensor was on ATmega 8 microcontroller.