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Video monitoring of the patient position in the intensive care units is complicated by the obstacles covering the patient body. Conventional posture detection algorithms do not work in this case. A reformulation of the posture detection problem for the case as an object detection/image classification problem and the use of recent deep learning techniques allowed us to achieve 94.5% accuracy on a pre-clinical test classifying 4 postures using imagery from an off-the-shelf camera and edge processing, which is a 60% improvement over the result previously known in literature. This in turn allowed us to build a ready for the clinical trials system based on inexpensive off-the-shelf cameras.Clinical Relevance - A cheap and practical system of automatic video monitoring of bedridden patients allows to minimize the risks of pressure ulcer in ICU.

The aim of the work was to develop a model of a knowledge base of an information system that collects information from various social networks. The model should improve search efficiency and facilitate the unification of data from heterogeneous sources. The work presents an ontological model for the unification of data profiles of different social networks. This model avoids data redundancy by including contextual information in annotations to ontology relations. In addition, an approach to information retrieval using syntagmatic patterns in the formation of a database tree of posts of social network users is proposed. The article also presents the results of experiments with data from the social network Facebook confirming the effectiveness of the proposed models and algorithms.

The work presents an ontological model for the unification of data profiles of different social networks. This model avoids data redundancy by including contextual information in annotations to ontology relations. In addition, an approach to information retrieval using syntagmatic patterns in the formation of a database tree of posts of social network users is proposed. The article also presents the results of experiments with data from the social network Facebook confirming the effectiveness of the proposed models and algorithms.

The calculation of the dynamic and energy characteristics of pulsed linear electromagnetic machines, made even according to simple structural schemes, is usually a complex and time-consuming task, due to the need to solve nonlinear differential equations. With the complication of structural schemes, the difficulties of solving these problems increase. In this regard, it is of interest to use the principle of reciprocity, which is one of the generalized methods of scientific knowledge of physical processes in dynamical systems, to solve the problems posed. According to this principle, the static characteristics of a pulsed linear electromagnetic motor are used as initial data and the impact energy of such an engine is directly determined by its static traction characteristics and integral work. The relevance of the study is due to the need to determine the energy and dynamic characteristics of the design of an electromagnetic motor with a gravitational energy storage. A counterweight is used as a drive. The parameters of such a design scheme are the static traction force of a pulsed electromagnetic motor, as well as the mass of the armature of the motor and counterweight. Based on the relationships of the reciprocity principle for electromechanical systems, expressions are obtained for the impact energy, the engine arm speed per minute and the shock power of a single-winding electromagnetic motor. It is established that the impact energy and dynamic traction of such an engine are proportional to its static traction. Whereas the engine armature frequency and its impact power have extremes at certain values of static traction and depend on the mass of the counterweight. Moreover, the maximums of the stroke frequency and impact power are biased towards large counterweight masses. It is advisable to use the obtained energy and dynamic characteristics of the structural design of an electromagnetic motor with a gravitational storage device to compare this design with other known structural designs in terms of the presented parameters.

In this paper the features of semantic and sentiment analysis of textual data of social networks are presented, and an original model and algorithm for sentiment analysis of textual fragments of social networks using fuzzy linguistic ontology are proposed. This approach involves the use of various subgraphs of fuzzy ontology when considering texts of various subject areas with regard to contexts. In addition, the algorithm involves the assessment of the sentiment scores of individual syntagmatic structures into which the analyzed text fragments are divided. It also presents the results of experiments comparing the efficiency of the developed algorithm with a group of existing approaches in analyzing text fragments on the example of data from the social network VKontakte.

The article studies the impact of reducing the resolution of an analog-to-digital converter of a digital receiver on the phase difference measurement error by the method of statistical modeling. Dependencies of the phase difference measurement error on the ratio of signal-carrier frequency and sampling frequency are shown. Dependencies of frequency-band maximum and frequency-band average phase difference measurement error on signal-to-noise ratio are provided. The results are given on modeling for analog-to-digital converter resolution of 8, 4, 2, 1 bits at the change of signal-carrier frequency within the range of 0.125 to 0.375 of sampling frequency, and the change of signal-to-noise ratio from −5 to 50 dB. The main peculiarities of the phase difference measurement error in case of small resolution of an analog-to-digital converter of a digital receiver are outlined, and recommendations on reducing it are worded.

The features of linear electromagnetic motors in the drive of impact machines are the impulsive and two-step nature of energy transformation. At the first stage, there is an electromagnetic transformation, that is, the accumulation of magnetic energy in working gaps. On the second stage, its transformation into mechanical work, that is, a magneto-mechanical transformation. Both these processes are separated in time they pass with varying degrees of restoration of the magnetic energy of the working gaps when the armature moves. During the working stroke of the armature, the trajectory of the motion of the operating point on the energy plane “current linkage - current” makes it ratio to establish the relationship between the mechanical operation of the engine and its residual magnetic energy. This ratio determines the magnetic efficiency. He, along with mechanical work, characterizes the efficiency of the magneto-mechanical energy conversion. The analysis shows that some of the energy regimes of the electromagnetic motor have low values of specific mechanical work. The urgency of the study is caused by the need to determine the magnitude of the magnetic efficiency for known energy modes and to find the best among them. For each of the regime known a mechanical method and residual magnetic energy per cycle were found by a known graphical method for determining the magnetic efficiency. This allowed us to compare the magnetic efficiency of each of the regime of the electromagnetic motor with the same residual magnetic energy. It is established that the magnetic efficiency of such an engine depends both on the design and mode parameters and on the coefficient of restoration of magnetic energy during the movement of the armature. Therefore, the twofold designs of the magnetic system of the electromagnetic motor make it possible to increase the efficiency of the magneto-mechanical transformation of such engines by 50 percent or more in comparison with single-gap engines. The best of the considered modes will be the energy regime with constant flux linkage while moving the armature and simultaneously decreasing the winding current of the motor. In this case, the magnetic efficiency approaches unity.

This article describes the method of building a domain ontology based on the linguistic analysis of content of text resources. Also an example of the proposed approach and the architecture of our pipeline presents. Representation of the problem area (PrA) in the form of an domain ontology is often used in the process of development of intelligent software systems and used as a knowledge base. The process of building an ontology is complex and requires an expert in the PrA. A large number of researchers are working to solve this problem. The basis of our approach is the use of a pipeline of different linguistic methods of text analysis. The set of rules developed by us is used to build an ontology based on the content analysis of a text resource.

The overhead power transmission line diagnostics is a part of a current production operation of electric grid company. The list of diagnostic types has to be developed on the basis of technical and economic factors. The solution of technical tasks is primary, and the additional diagnostic types should be used if the cost advantages are available. One of the assessment methods for overhead power transmission line diagnostics is described in the paper. The assessment technique for overhead power transmission lines economic efficiency diagnostics is considered and its cost advantages calculation is given.

Open-ended questions are questions that allow someone to give a free-form answer. Analysis and evaluation of answers to open-ended questions requires automation. Experts who develop standards of free-form answers use uncertain information. Uncertainty may appear in cases of synonymy, polysemy, insufficiency or redundancy of the object description. Therefore, fuzziness is the most common type of uncertainty in activities related to the evaluation of answers to open-ended questions. This paper describes the methodology for evaluating free-form answers using knowledge discovery methods. Methods of knowledge discovery consider the uncertainty and fuzziness in the answers to open-ended questions.

Generation adequacy indices (GAI) calculations are performed not only for electrical power system development problems but also for on-line control problems. Liberalization of power and energy market along with increased focus on renewable energy sources, which is motivated by both ecological and economical incentives, has led to comprehensive changes in power systems. Practically, the main mathematical method for calculating GAI of an electrical grid with complex structure is Monte-Carlo simulation (MCS) technique. It can provide sufficiently accurate results, but the simulation consumes really huge amount of computational time, especially for large power systems. Generation capacity that has to be installed in a power system for meeting reliability criteria depends not only on system demand but also on generation mix. The problem at hand is to improve computational efficiency of the GAI calculating technique without decrease in calculations accuracy. In order to solve the problem, this paper proposes an analytical method for GAI calculations, that is referred to as supplied demand algorithm (SDA). The paper compares the MCS technique and the SDA. The analyzed methods have been developed using the C# and VBA programming language. Input data for the methods includes generation mix data, generation and load probability indices. The comparison results allow to select the proper method for the GAI calculations and show the main factors that affect the resulting GAI.

The article considers the main construction principles and an architecture of the unified platform for data mining. The methodology for organizing output of recommendations on estimation of organization financial management indices over a number of reporting periods on the expert level is investigated. The methodology is based on the estimation of trends characters of the corresponding indices and the inference of linguistic values of corresponding objects properties of the applied ontology. The methodology also allows to construct the expert opinions of both current state of organization indices and forecasting one obtained by the application of the F-transform algorithm. The object of the analysis is a commercial organization. The modeling process is the output of expert opinion on the financial management of the object under consideration.

The key feature of linear electromagnetic motors in the drive of shock machines is a pulsing nature of energy transformation. The process of magnetic energy accumulation and its transformation to mechanical work are divided in time, proceed iteratively and with various degree of magnetic energy restoration. It causes an inefficient energy transformation and low values of mechanical work per unit of mass of the motor. The conducted research of the conditions of energy transformation and the operating mode of such motors allowed one to reveal seven elementary magnetic cycles which represent energy modes with various correlations of magnetic and mechanical energies. The research relevance is justified by the necessity to define the size of mechanical work for each of the energy modes and search for modes with the largest mechanical work among them. For each of the considered energy modes expressions the mechanical work has been found by the known graphic method. It allowed one to compare mechanical work values for each of the motor modes at the same residual magnetic energy. It was found that mechanical work of the motor depends both on structural and control parameters. Therefore, two-split designs of a magnetic system allow increasing mechanical work of motors 3-4 times as compared with one-split. The best of considering modes is the energy mode with constant magnetic-flux linkage and dropping current of winding of the motor.

The paper focuses on the possibility of optimizing the district heating supply in the market conditions with constantly changing parameters and stochastic behavior of the electricity market prices, fuel prices and weather conditions. The possibilities of independent work of companies and cooperation for more benefits are also reviewed. As possibility of distributing the additional profit in the case of coalition, the methods of the cooperative game theory are used. In this paper the authors examine and compare the options of the formation of coalitions, compare the selected alternatives and analyze the possible profits of the market participants in the case of different models of behaviour. The proposed options of solving district heating optimization problems and calculation examples are based on the current situation of the real European city.

The article describes the work of a pulsed electromagnetic linear engine according on each of the seven energy regimes. Each of the modes differs to extent of restoration of magnetic energy at the movement of an anchor of the engine. To this end, ranges of magnetic energy recovery coefficient, defining the boundaries of energy regimes have been established. The analytical method has received the generalized expressions of current of excitement, electromagnetic traction effort, speed of movement of an anchor of the engine and mechanical power as movement of an anchor. The specified electromechanical characteristics of the engine correspond to a design of magnetic system of the engine with a longitudinal magnetic field. Characteristics allow to execute comparison of power and dynamic properties of pulse linear electromagnetic engines in each of seven power modes. Such comparison will help to reveal both the undesirable, and rational modes of the electromagnetic engine, for example, with the best stability of energy of the working course of an anchor.

Relevance of research is caused by need of an assessment of the extreme magnetic energy reserved in working gaps of the electromechanical converter of electromagnetic type at saturated magnetic system at a stage of start-off of an anchor. As the electromechanical converter the pulse linear electromagnetic engine can be used. Such assessment will allow to reveal ways of increase of specific power indicators of pulse linear electromagnetic engines. By means of the offered approximation of a curve of magnetization of a magnetic conductor of the converter the sedate polynom of the ninth degree has analytically received dependence of extreme magnetic energy on design data of the converter. It has allowed to estimate influence of initial inductance of the converter and extent of saturation on the reserved magnetic energy. So, at change of the generalized design data from 45° to 25° that corresponds to transition from magnetic system, one-shameful into a two-shameful design, the size of extreme magnetic energy of pulse linear electromagnetic engine will increase three and more.

This The paper looks at the process of solving tasks related to district heating at the conditions of market and uncertainty. Here, the possibilities of individual and cooperative behaviour of different market participants are also reviewed. For substantiating the rationality of the decisions and distributing the additional profit in the case of joining companies, the methods of the cooperative game theory are used. The paper reviews the possible alternatives in the formation of coalitions, compares the selected alternatives and analyses the possible profits of the market participants in the case of different models of behaviour. The proposed strategies and calculation examples are based on the existing district heating system of a real European city.