Вимірювальна техніка та метрологія. – 2015. – Випуск 76

Permanent URI for this collectionhttps://ena.lpnu.ua/handle/ntb/32930

Міжвідомчий науково-технічний збірник.

Вимірювальна техніка та метрологія : міжвідомчий науково-технічний збірник / Міністерство освіти і науки України ; відповідальний редактор Б. І. Стадник. – Львів : Видавництво Львівської політехніки, 2015. – Випуск 76. – 165 с. : іл.

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    Томографічний метод вимірювання просторового розподілу температури за результатами вимірювань опору лінійних резистивних перетворювачів
    (Видавництво Львівської політехніки, 2015) Дорожовець, Михайло; Бурдега, Мар’яна
    Проаналізовано можливості реконструкції температурного поля на поверхні стінки томографічним методом за результатами вимірювання опорів лінійних резистивних перетворювачів температури. Опрацьовано модель апроксимації просторового розподілу питомого опору залежно від температури алгебраїчними двовимірними многочленами порядку 4 і 5. Сформовані матриці коефіцієнтів лінійних систем рівнянь, що описують шуканий просторовий розподіл питомого опору чутливих елементів від результатів вимірювань опорів чутливих елементів вздовж лінії їх розміщення на об’єкті дослідження. Моделюванням досліджено якість відтворення просторового розподілу температури томографічним методом з використанням мідних чутливих елементів. Встановлено, що за кількості вимірювань 54 та 96, а також за порядків многочлена 4 і 5 під час відтворення просторового розподілу температури у вигляді косинусної та гауссівської двовимірних моделей середньоквадратична зведена похибка становить від 0.65% до 1.55% , а максимальна зведена похибка відтворення – 1.25–9.35 %. Проанализировано возможности реконструкции температурного поля на поверхности стенки томографическим методом по результатам измерения сопротивлений линейных резистивных преобразователей температуры. Обработано модель аппроксимации пространственного распределения удельного сопротивления в зависимости от температуры алгебраическими двумерными многочленами порядка 4 и 5. Сформированы матрицы коэффициентов линейных систем уравнений, описывающих искомое пространственное распределение удельного сопротивления чувствительных элементов вдоль линии их размещения на обьекте исследования. Путем моделирования исследовано качество воспроизведения пространственного распределения температуры томографическим методом с использованием медных чувствительных элементов. Установлено, что при количестве измерений чувствительных элементов 54 и 96, а также при порядке многочлена 4 и 5 во время воспроизведения пространственного распределения температуры в виде косинусной и гауссовской моделей среднеквадратичная приведенная погрешность составляет от 0.65% до 1.55%, а максимальная приведенная погрешность воспроизведения от 1.25% до 9.35%. In the article the review of measurement problems related to spatial temperature distribution at various industrial facility is carried out. In particular for furnace, rubbish burning stove and walls of building structures. For these measurements acoustic and optical tomography are often used. In particular for spatial temperature distribution at furnace and rubbish burning stove acoustic tomography are used. To measuring the spatial temperature distribution of liquid medium ultrasound tomography is used. The disadvantage of the acoustic tomography is that the trajectory of acoustic waves greatly depended on the temperature distribution of an object. In the case of using screening, these methods aren’t used. In this article, the possibilities of reconstruction of temperature field on the surface of the wall using tomography method based on results of measurement of the resistance of linear resistive temperature sensors are analyzed. One of the possible ways of placing of the sensitive elements on the rectangular surface is reviewed (Fig. 1). Fig. 2 shows the generalized line along which the resistance of sensing element can be calculated. The resistance of linear resistive temperature sensors depending on resistivity are presented by equation (3). The resistance of linear resistive temperature sensors along line l j except vertical lines are presented can be calculate by equation (5), and resistance for vertical lines can be calculated by equation (6). The approximation of the spatial distribution of resistivity of sensitive elements two-dimensional function is present by equation (7). Coefficients’ matrices of systems of linear equations that describe desired spatial distribution of sensitive elements resistance from the results of resistance measurements of sensitive elements along the line of their placement on the subject of research were formed (equation 10). Coefficients’ vector of the basic functions were calculated using the method of least squares (equation 12). Approximated spatial temperature distribution can be calculated on the basis of approximation model of the spatial distribution of resistivity (equations 16 and 17). In the article proposed method is investigated for sensitive elements with the following parameters: resistivity ρ0 = 0.01724 μΩ m, temperature coefficient of resistance α = 4.3∙10-3 1/ºС, diameter of sensitive element d = 0.2 mm is simulated. The wall size of 6×6 m×m is investigation. Three approximation models of the temperature distribution in the form of two-dimensional cosine, Gaussian and asymmetrical functions with initial temperature Θ0 =100 ºС and maximal change temperature Θm = 75 ºС are used. For these temperature distributions and set parameters of sensitive elements the measured resistances sensitive elements (equation 21) are calculated. Using simulated results (equation (12) and (7)) the spatial distributions of resistivity are reconstructed. Also the spatial temperature distribution using simulated results is reconstructed (equation (17)) and presented in Fig. 4. The maximum modulo and root mean square characteristics errors of reconstructed temperature are calculated (equation (22), (23)) and presented in table 2. Found, that for 54 and 96 measurement results and for algebraic polynomials 4 and 5 order root mean square error of reconstruction of temperature field varies from 0.65% to 1.55% and maximum modulo error of reconstruction of temperature field varies from 1.25% to 9.35%. In conclusion, the reconstructed image of temperature depends on the number of linear resistive sensitive elements and also of order of polynomial approximation functions.
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    Про використання сейсмічних хвиль Релея в охоронних системах
    (Видавництво Львівської політехніки, 2015) Рак, Володимир
    Запропоновано використання сейсмічних хвиль Релея у охоронних системах сигналізації, які, крім ідентифікації порушення охоронного режиму, дадуть змогу визначати координати цього порушення. Проведено оцінку зони чутливості таких систем та визначено напрями подальших експериментальних досліджень з метою встановлення доцільності їх практичної реалізації. Предложено использование сейсмических волн Рэлея в охранных системах сигнализации, которые, помимо идентификации нарушения охранного режима, смогут определять координаты этого нарушения. Проведена оценка зоны чувствительности таких систем и определены направления дальнейших экспериментальных исследований с целью установления целесообразности их практической реализации. There are four types of seismic waves: primary waves , secondary waves , wave Rayleigh and Love waves. The first two types are called depth waves, because these waves penetrate into the depths of the earth. Rayleigh waves and Love waves called surface waves. They can to propagate on the surface. Given the characteristics of propagation of these waves can be concluded that even at low energies excitation source, Rayleigh waves can propagate at a much greater distance than depth waves, so it would be advisable to use them in security systems. Knowing the velocity of the waves, which is measured the sensors, the ratio of amplitudes and time delays with which they come, we can determine the coordinates of the source of vibration. The output voltage of existing sensors (seismometers) is a function of frequency seismic waves and their amplitudes. This may be the cause of the error. Autor is suggested another principle of the sensor, output signal of which is a function only of the amplitude. Is posted conversion function of sensors and dependence on the sensitivity threshold. If we know threshold of the sensitivity of the sensors, with certain assumptions, we can estimated distance from which capacitive seismometer feels seismic waves excitedWalking man at different values of the coefficient of energy absorption of seismic waves geological environment. For seismic exploration seismic surface waves are interference. Most likely, thismay explain the lack of information about the amount of energy that falls on the formation of surface waves and the dependence of this quantity on the power source. Zone of sensitivity may be limited to so-called microseisms arising from soil vibrations caused by fluctuations of the trees, transport, and industry. To limit the impact of microseisms be appropriate to apply filters. Therefore, before decision about the possibility of practical implementation of such systems, data relating to the area of sensitivity of seismometers need additional experimental verification in the field where necessary to experimentally explore: how much energy of the source belongs Rayleigh waves and Love waves ; energy distribution between surface waves; by the ratio of amplitudes determine the absorption coefficient of surface waves for areas where the security system will be used.
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    Аналіз шкал вимірювань
    (Видавництво Львівської політехніки, 2015) Мотало, Василь
    Розглянуто й проаналізовані основні питання теорії та принципи систематизації типів шкал вимірювань. Розглянуто види властивостей емпіричних об’єктів та особливості їх прояву і відповідні їм шкали вимірювань. Вибір і використання тієї чи іншої шкали і, відповідно, методики вимірювання залежить від виду вимірюваної величини та способу отримання вимірювальної інформації, тобто способу порівняння розмірів величин. Рассмотрены и проанализированы основные вопросы теории и принципы систематизации типов шкал измерений. Рассмотрены виды свойств эмпирических объектов, особенности их проявления и соответствующие им шкалы измерений. Выбор и использование той или иной шкалы и, соответственно, методики измерения зависят от вида измеряемой величины и от способа получения измерительной информации, т. е. способа сравнения размеров величин. The basic principles of systematization of measurement scales types are describes and analyses in this article. Properties types of the empirical objects and corresponding measurement scales are considered. According to VIM3 (“International vocabulary of metrology: Basic and general concepts and associated terms”), measurement scale (quantity-value scale) is an ordered set of quantity values of quantities of a given kind of quantity used in ranking, according to magnitude, quantities of that kind, for example, Celsius temperature scale, time scale, Rockwell C hardness scale etc. According to the metric determination, depending on the type of the investigated empirical object, in particular, of its properties, and therefore the type of measured value, measurement scales are divided into the following types: nonmetric scales: nominal scales and ordinal scales; metric scales: intervals scales, ratios scales and absolute scales. Metric scales – these are scales, which have the units of measurement (for eg., meter, ampere, m/s). Non-metric scales – these are scales, which do not have units of measurement. According to the form of empirical data obtaining, measurement scales are divided into verbal, numerical and graphic. According to the number of the displayed properties of empirical objects, measurement scales are divided into onedimensional and multidimensional. Nominal scales are formed in the case when a certain property of empirical objects is evident only in respect of equivalence. The main informative parameter of such objects is their quantity (number), which is determined by counting. This feature can be displayed by any number or other mark that does not contain any information about the value size, which is inherent in this property. Nominal scales or scales of names are used in the measurement of objective evidences such as odor, color, blood groups, nationality, marital status, age, gender, work experience, qualifications, telephone numbers, passports, bar codes of products, etc. Ordinal scales are formed in the case when a certain property of empirical objects is shown in relation of equivalence and order (of level). Located according to ascending or descending order, namely, according to the rank, the size of the measured values constitute ordinal scale or rank scale. The ordinal scale or rank scale is expressed in the form of an ordered sequence of points, marked with letters, numbers or symbols that meet certain values size Qі, і=1,2,3,…,п: Q1
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    Метрологія, кваліметрія та кваліметричні вимірювання: теорія і практика
    (Видавництво Львівської політехніки, 2015) Мотало, Василь; Мотало, Андрій; Стадник, Богдан
    Розглянуто й проаналізовані основні проблеми розвитку кваліметрії. Обґрунтовано використання в теорії та практиці кваліметрії концептуального поняття “кваліметричні вимірювання” як одного із видів вимірювань, що дозволяє поєднати методологію кваліметрії та метрології, істотно розширити можливості кваліметрії щодо достовірності й точності отриманих оцінок якості продукції. Розглянуто і проаналізовано основні завдання кваліметрії з оцінювання якості вуглеводневих газів. Рассмотрены и проанализированы основные проблемы развития квалиметрии. Обосновано использование в теории и практике квалиметрии концептуального понятия “квалиметрические измерения” как одного из видов измерений, что позволяет совместить методологию квалиметрии и метрологии и существенно расширить возможности квалиметрии в достоверности иточности полученных оценок качества продукции. Рассмотрены и проанализированы основные задачи квалиметрии в области оценивания качества углеводородных газов. In the article, the main issues of interrelation between qualimetry and metrology reviewed and analyzed. Qualimetry is a branch of science where research subject is product quality quantitative assessment and as an each new science it has some theoretical and methodological problems. Solving these problems, according to the authors, is possible only in a complex combination of quality control methodology and metrology. Metrology, the science of measurement and its application, has the strong scientific, practical and legal tools, which allows research in any field of knowledge. Analysis of the ways of solving these problems is the subject of this study. The authors propose to use the concept of “qualimetrical measurements” as one of the types of measurements in the theory and practice of quality control. That allows combine the methodology of qualimetry and metrology and significantly extend qualimetry opportunities in the reliability and accuracy of the product quality estimates. Qualimetrical measurements, by the authors definition, is indirect measurements of product quality level, the meaning of which can be obtained by the way of measurement results processing of its characteristics according to multidimensional scaling methodology. Product quality level is a relative characteristic of product quality grounding on the comparison of values of products quality assessed indexes and basic values of corresponding indexes. Generally, qualimetrical measurements as any other one consists of two principal stages: • carrying out the measuring experiment during which different characteristics (mechanical, dimensional, electric, magnetic, thermic and chemical composition etc.) of studied products are measured; • measuring experiment results processing during which the studied products quality Q is defined. This is the qualimetrical measurements results. Therefore, the mentioned above approach of qualimetrical measurements essence and purpose enables to treat them as one of the indirect measurements types and to use the main principles of measuring theory for their analysis. The procedure of qualimetrical measurements for measuring of product quality level is developed and its practical implementation described in this article and such tasks of research to achieve the work goal solved: • a synthesis of the product quality measure; • developing of the procedure of qualimetrical measurements; • a synthesis of the one-dimensional qualimetrical scale of product quality level; • a practical implementation of the qualimetrical measurements methodology on the example of the determining the quality level of natural gas as an energy source. The basis of any measurement is the comparison ofmeasured value and measure which reproduce and (or) keeps one ormore known values of a given quantity. Qualimetrical measurements specificity is absence of specific physical (material) quality measures of some products. Product quality virtual measure used formethodological providing of qualimetricalmeasurements procedure realization and their accuracy and quality assessment. Virtualmeasure is the theoretical analog of corresponding physical (material)measure of studied product and it’s the reflection of real physical (material) measure of current product quality is expressed by mathematical and programmeans. In this case, the product quality virtualmeasure is a weighted basic profile of product qualityPK,bz , formed from single relative weighted basic quality indexes Kbz,i , і = 1,2,…,п, where n – number of product quality indexes, equal to the number of properties of the investigated product. To measure the quality level of the investigated product Q, namely for full implementation of qualimetric measurements procedures, it is necessary to compare the weighted estimated profile of product quality PK,oz , formed from single relative weighted estimated quality indexes Koz,i , with weighted basic profile PK ,bz , namely with virtual quality measure. To compare profiles of quality PK,oz and PK,bz is used the methodology ofmultidimensional scaling – one of the sections of mathematical statistics, the subject of research of which is data processing on pairwise similarities, connections and relationship between objects that are analyzed in order to present these objects in the form of points of some multidimensional space. In the case of statistic independent (non-correlated) single relative quality indexes for comparision profiles of quality PK,oz and PK,bz it should be used weighed Euclidean individual differences model. In the case of correlation between the single quality indexes to determine product quality level it should be used three-model multidimensional scalingmodel. In both cases it should be defined the absolute difference or deviation function DП between profiles of quality PK,oz and PK,bz . On the basis of obtained deviations DП the scale of product quality level Q determination can be build, and as result bigger numerical quality Q level value will correspond for higher product quality: Q = 1 –DП or Q = (1 –DП)×100%. Thus, based on the methodology of qualimetrical measurements, developed in the article, the complex evaluation of the Natural Gas quality as an energy source was realized, in which were taking into account a ratio of themost important gas characteristics, such as caloric content, humidity, density, composition, availability and quantity of non-flammable and harmful components.
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    Оцінювання стандартної непевності типу “В” на основі складових адитивної та мультиплікативної похибок
    (Видавництво Львівської політехніки, 2015) Васілевський, Олександр
    Запропоновано спосіб перерахунку адитивної та мультиплікативної складових похибок, аналітичні вирази яких отримуються розкладанням відповідного рівняння перетворення у ряд Тейлора, в стандартну непевність типу В. Цей спосіб апробовано під час оцінювання статичних характеристик засобу вимірювання кутової швидкості. Він дає змогу представляти характеристики точності засобів вимірювань відповідно до вимог міжнародних стандартів з оцінювання якості вимірювань. Предложен способ пересчета аддитивной и мультипликативной составляющих погрешностей, аналитические выражения которых получают путем разложения соответствующего уравнения преобразования в ряд Тейлора, в стандартную неопределенность типа В. Этот способ апробирован при оценке статических характеристик средства измерения угловой скорости. Он позволяет представлять характеристики точности средств измерений в соответствии с требованиями международных стандартов по оценке качества измерений. A method for conversion additive and multiplicative constituents of errors, analytical expressions are obtained by decomposition of the corresponding transformation equations in Taylor series in a standard uncertainty of type B. Decomposition of transformation equations used means of measuring in the Taylor series allows to obtain analytical expressions of basic static characteristics of the means of measuring on the basis of which it is possible to explore the characteristics of changes in the sensitivity of means of measuring, the nominal conversion function, influencing coefficients, additive and multiplicative errors in a deviation of influencing parameters on their nominal values. This method has been tested in the evaluation of static characteristics of measuring angular velocity. It allows you to represent the characteristics of precision of means of measurements in accordance with the requirements of international standards to assess the quality of measurements. These mathematical expressions allow investigation of basic metrological characteristics of a measuring angular velocity, and the causes and conditions that lead to increased measurement errors in the angular velocity of electric motors to be identified. To represent standard uncertainty of type B, which is caused by the presence of additive and multiplicative errors in the measurement means, mathematical expressions are proposed that allow recalculation of these errors to standard uncertainty. The mathematical expressions were tested using the example of the recalculation of additive and multiplicative errors of the measurement means of the torque in the standard uncertainty of type B. The resulting mathematical tools and characteristics of change of the basic static metrological measuring means for angular velocity give us the opportunity to identify the causes of increase in error in the measurement of angular velocity in electric motors. This enables us to explore how to diminish or eliminate them, and also to synthesise measuring means angular velocity with standardised metrological characteristics. To convert received instrumental error components measuring angular velocity in a standard uncertainty of type B and presentation characteristics of precision measuring instruments in accordance with the requirements of international standards to assess the quality of measurements suggested model equations given in the article. On the basis of the proposed model equations executed counts additive and multiplicative error components measuring the angular speed of the combined standard uncertainty of type B, which is caused by the presence of the instrumental components of errors in deviation vlyayuschih magnitude of its nominal value. The studies found that the type B standard uncertainty is 3.38 rad/s in the range of conversion from 0 to 100 rad/s rejecting influence quantity β from its nominal value of 0.01 radians.
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    Дослідження акустичних методів вимірювання температури в рідинах
    (Видавництво Львівської політехніки, 2015) Петровська, Ірина; Івах, Роман; Сопрунюк, Анастасія
    Досліджено можливість вимірювань температури у воді із застосуванням двох акустичних методів: ехо-пульс і часоімпульсного. Для проведення вимірювань використано потоковий канал, через який пропускали воду, температура якої змінювалась і вимірювалась з використанням ультразвукових сенсорів. Встановлено залежність температури води від параметрів ультразвукового сигналу. Проведені дослідження показали, як саме змінюється швидкість звуку у воді зі зміною температури у ній. Наведено графік отриманого сигналу зі зміною температури від 10 °С до 60 °С. Исследована возможность измерений температуры в воде с использованием двух акустических методов: эхо-пульс и время-импульсного. Для проведения измерений использовано потоковый канал, через который пропускали воду, температура которой изменялась и измерялась с использованием ультразвуковых сенсоров. Выявлено зависимость между амплитудой и временем ультразвукового сигнала. Проведенные испытания показали, как именно изменяется скорость звука в воде с изменением температуры в ней. Представлено график полученного сигнала с изменением температуры от 10 °С до 60 °С. In this work the subject of the research is the average temperature of liquids by using two acoustic methods: echo-pulse method and time-pulse method. For conducting the measurements the flow channel is used, through which water was passed, the temperature of which has changed and which must be measured. For the temperature measurements ultrasonic sensors are used, which are fixed on both sides of the current channel. The calculation of the special design of the mounting is made and the ultrasonic sensors are chosen. The size estimation of the glass coupling rod is made, based on the average temperature of the glass cylinder, thermal resistance, cylindrical glass square.The block diagram is presented for measuring the passage time of the ultrasonic signal in the measuring channel, according to which the transmitter and receiver are in direct contact with the pipe. For better contact ultrasonic gel was used. In addition, the oscilloscope to measure audio signals and device for generating acoustic pulses and their measurement using echo-pulse method are used. The results of studies using the echo pulse and the time-pulse methods are presented. The first measurement of the echo-pulse method was performed using the ultrasonic sensor on the pipe when the flow of water is active and the temperature of the water in the thermostat is fixed in the range from +10 C to 60 °C. The second dimension using this method is conducted when the flow of water is inactive in conditions of the same temperatures. The obtained results of measurements using the time-pulse method with an oscilloscope and an exemplary device when the temperature changes from 20 °C to 60 °C in increment of 10 are presented. The graphs of the dependencies obtained for all investigated temperatures are depicted. It is revealed that the current times of the sound pulses with increasing temperature are short. The chart is moved to the left. The signal on the oscilloscope screen in conditions of 60 °C is received. The first channel shows the audio signal acquiring with an exemplary device. The second channel shows the measuring signal. The next measurement is made with a glass cylinder, which is placed between the pipe and the ultrasonic sensor. The results of measurements using a glass cylinder in the temperature range from 20 °C to 60 °C are presented. The results of the carried out measurements show how the amplitude of the ultrasonic signals with a signal change is modified. Having this change it is possible to find the temperature which is needed to be determined. By using oscilloscope the dependence between amplitude and time of the ultrasonic signal is revealed. Studies have shown in which way the sound speed in water is changing with its internal temperature change.
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    Інтелектуальний кутовий сенсор для антенних систем та його метрологічний аналіз
    (Видавництво Львівської політехніки, 2015) Паламар, Михайло; Чайковський, Андрій; Лупенко, Анатолій
    Запропонована електронно-оптична схема, конструкція та алгоритм функціонування оптоелектронного сенсора абсолютних кутових положень з функціями виявлення та компенсації низки похибок, що виникають у механічних вузлах обертового механізму, за допомогою опрацювання інформації мікроконвертором у самому сенсорі. Виконано метрологічний аналіз сенсора й оцінку джерел похибок за результатами моделювання та експериментальних досліджень. Інтелектуальний сенсор орієнтований на використання у системах керування наведенням антенних комплексів космічного зв’язку. Предложена электронно-оптическая схема, конструкция и алгоритм функционирования оптоэлектронного сенсора абсолютных угловых положений с функциями обнаружения и компенсации ряда погрешностей, возникающих в механических узлах вращающегося механизма, путем непосредственной обработки информации микроконвертором в самом сенсоре. Проведен метрологический анализ сенсора и оценка источников погрешностей по результатам моделирования и экспериментальных исследований. Сенсор ориентирован на использование в системах управления наведением антенных комплексов космической связи. The design and electron-optical scheme of intelligent opto-electronic sensor of absolute angular position are proposed. The sensor is completed by microconverter for data processing to implement the detection and compensation a number of errors that caused by mechanical nodes of rotating mechanisms. The principle of the operation of proposed angle sensor are based on themethod of determining the absolute angular position using a code disk with one track. Pseudorandom code sequence of track is composed of different widths sectors. The code reading and processing is realised by means of two single-line photo-matrices located at the ends of the chord of the disk. The code sequence is constructed so that any fragment of sectorswhen projected on photo-matrix is unique and occurs only once in passing the code sequence on the disk. To accurately determine the angular position the algorithm of the sub-pixel processing image is used. It allows determine the distance to the edges of the sectorswith resolution ability higher than half of the pixel width, that is equal of 2 micrometer. The resolution ability in the angle determination by sensor is increased to 16 bits. Due to the sensor design features, such as usage of two opto-electronic channels and software implementation of algorithms for processing information from photo-lines, errors caused by mechanical nodes of sensor via disk offset and eccentricity are minimized. Measuring at the proposed scheme also avoids the influence of random displacement sensor axis due to backlash in the bearings. The resolution ability of the designed sensor is 20 arcseconds. Based on simulation results and experimental studies metrological analysis of sensor and evaluation of error sources are given. Intelligent sensor in design and functionality was designing for the usage in control systems in particular in the pointing and tracking the antenna of the space communication systems with a narrow directional diagram.
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    Моделювання та якість моніторингу діагностичних систем
    (Видавництво Львівської політехніки, 2015) Чабан, Олеся; Юзевич, Лариса
    Розроблено рекомендації щодо поліпшення якості математичних моделей моніторингу складних об’єктів техніки та медицини з низьким рівнем динаміки процесів, що характеризуються особливостями раннього виявлення кризових (передаварійних) ситуацій. Разработаны рекомендации относительно повышения качества математических моделей мониторинга сложных объектов техники и медицины с низким уровнем динамики процессов, которые характеризуются особенностями раннего выявления кризисных (предаварийных) ситуаций. The example of improvement of the mathematical model of monitoring of difficult objects of technique and medicine with the low level of dynamics of processes is examined. The article of researches is normative documents, which should be expediented to specify and perfect on the basis of thein formation, got as a result of analysis of results, mathematical models of monitoring of difficult objects of technique, medicine got with a help with the low level of dynamics of processes. An aim of the put article is an evaluation of quality of theim proved mathematical model of monitoring of difficult objects of technique, medicine with the low level of dynamics of processes. As an example, the diagnostic system of the corrosive monitoring of pipelines (SCMP) is examined, the methodologies described and regulated by a state standard are fixed in basis of functioning of that. Facilities of SCMP are diagnose the stress corrosive spalling of pipelines, that is initiated and develops as defects on the external surface of pipe at using of isolating coverage and cathode defence for simultaneous influence of the mechanical loading and corrosive-active environment. A corrosive environment is designed by an aquasystem with the different value of pH-value. The criterion of damage of sheeting the methods of measuring of protective and polarization potentials is a jection of electric potential, that is compared to the value, set corresponding normative document. It is suggested to use methodology of control of constituents for slushing coverage on the stage of making of steel pipes with coverage on the size of regional corner of moistening. Coverages can be metallic, dielectric. In particular, the three-stratified polyethylene coverage is used in the last time. On the size of regional corner of moistening it is possible to estimate adhesion of coverage, in particular, work of adhesion and energy of adhesive bonds. The criterion of adhesion strength for coverage (metallic or dielectric), that is expressed through the critical values of power descriptions of interface layer on the border of metal of pipe with coverage is introduced. The methods of scientific researches are constantly developed and improved. Therefore in course of time standards need additions, id est bringing of new more actual information. Touches such type of addition integral criterion of evaluation of biocorrosive aggressiveness of soils, that takes into account exceptelectro-resistance also a quantity most corrosive dangerous groups of microorganisms and elements of chemical composition of soils. Possible penetration of oxygen, water and other substances is through sheeting. As a result there is a hasp of passive tape with formation of local cells of corrosion – pitting. Pitting of transformed in microcrack, and on the finishing stage one of microcracks initiates distribution of main crack. Procedure of calculation of durability and longevity of pipeline is offered at presence of defects as a cavity there is pitting in the top of that. Methodologies of calculation of durability of steel pipes at presence of defects are complemented by the criteria of durability, that in the models of SCMP was not examined before. The first criteria represents connection of threshold value of coefficient of intensity of tensions of К1SCC with work off lowage in a calculation on unit of the accrued surface at distribution of crack of PPL and overstrain of anodic reaction z of corrosive dissolution. The parameter of PPL is included in the known formula (criterion of durability) of Griffits-Orovan, that it is also suggested to be used. The criterion of Griffits-Orovan binds the limit of fluidity (to durability) of metal to length of crack, by the Young’s module and by the Poisson’s ratio of material. The system of mathematical correlations of SCMP is suggested to complement correlation for the closeness of current of ia in the top of pitting, that is expressed through a corner in the top of pitting, conductivity of electrolyte, dependency upon resistance change of potential between anodic and cathode parts. This correlation is set forth as a criterion of corrosive firmness of pitting. The model of SCMP is complemented by criterion correlation for determination of speed of remaining corrosion of metal (id est closeness of Ik of corrosive current) in the defect of isolating coverage, polarization potential and potential of corrosion of metal of pipeline are included in that. The new entered criteria of durability and corrosive firmness complement, specify and perfect SCMP and can be used for control of corrosive process and development of recommendations of slushing defence. With their help optimization of terms of defence of elements of constructions of metallic underground pipelines can be conducted. The compatible use of the new entered criteria allows in detailen ough from positions of electrochemistry, physics of superficial processes and mechanics of destruction to study the mechanisms of distribution of corrosive cracks in main pipelines that are in aggressive environments. Monitoring quality is characterized by quality of measuring and recreation of information, in particular: by exactness, comparativeness, authenticity, operationability, stability of estimations of parameters, that is included in the new entered criteria. Recommendations in relation to upgrading of mathematical models of monitoring of difficult objects of technique and medicine with the low level of dynamics of processes touch protective potentials, them uncertainty and gradients. An algorithm that is base on the use of the new entered criterion correlations and allows to optimize oscillation of protective and polarization potentials in time is offered in the system of the corrosive monitoring of underground pipelines, that it is necessary for the correct evaluation of corrosive activity of soil and speed of remaining corrosion of metal of pipeline. Corresponding results give an opportunity to forecast the change of the corrosive state of metal of pipeline in course of time and to expect the resource of capacity of local area and all pipeline on the whole. The indicated innovations will help to perfect normative documents, in particular, standards that touch anticorrosion defence.
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    Розроблення та аналіз варіантів апаратної реалізації портативних частотних аналізаторів імпедансу
    (Видавництво Львівської політехніки, 2015) Стадник, Богдан; Хома, Володимир; Хома, Юрій
    Описано та проаналізовано три варіанти побудови портативних частотних аналізаторів імпедансу на сучасній елементній базі та розглянуто можливості їх використання в поєднанні із ПК, а саме: на базі спеціалізованих мікросхем AD5933/AD5934, сигнального мікроконтролера STM32F4, програмованої логічної матриці сім’ї Cyclone. Також наведено алгоритми функціонування ЧАІ, з описом процедур калібрування та визначення параметрів АВП, коригування та опрацювання результатів вимірювання. Описаны и проанализированы три варианта построения портативных частотных анализаторов импеданса на современной элементной базе и рассмотрены возможности их использования в сочетании с ПК, а именно: на базе специализированных микросхем AD5933 / AD5934, сигнального микроконтроллера STM32F4, программируемой логической матрицы семейства Cyclone. Также приведены алгоритмы функционирования ЧАИ, включающие описание процедур калибровки и определения параметров АИП, корректировки и обработки результатов измерения. Impedance spectroscopy is widely used to study biological, physical and chemical objects, for example in biomedical measurements, in study of the materials properties, particularly on micro- and nanoscale, for corrosion monitoring and diagnostics, for control of batteries, fuel cells. Often research is carried out on a objects under non-laboratory conditions. A good example of such research is the use of impedance spectroscopy for testing of corrosion-resistant coatings on various steel structures such as bridges, pipelines and other. This leads to the need for cheap, small portable measuring devices – impedance analyzers. A novel concept for design of portable impedance analyzers have been developed in the article. Themain idea is based on minimization of the analog part ofmeasurement channel, aswell as on the replacement of a number of functions to a personal computer. Three variants of design of portable impedance analyzers are described and analyzed in the article. The first option involves the use of single-chip converter AD5933, combined with universal processor Atmega16U2 and external operational amplifier. The hardware implementation is quite simple, but the main disadvantage is limited frequency band (maximum frequency converter AD5933 is 100 kHz). Also this approach has no possibility for tuning and optimization of measuring channel parameters. The second implementation of portable impedance analyzers is based on the STM32F4 digital signal controller with built-in DACs and ADCs, which makes it an extremely attractive in terms of flexibility and simplicity in the design. However, the drawback of this implementation includes limited frequency band (100 kHz). The third option involves the implementation of digital part of the impedance analyzer (CPU, DDS and DSP blocks) on FPGA in combination with external DAC and ADC. This method is the most flexible in terms of configuration, as the digital part enables optimization of measurement channel parameters and DAC and ADC specifications can be chosen according to current application needs. The main disadvantage of this approach is relatively high price and power consumption.
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    Ризики харчового ланцюга біологічно активних добавок (на прикладі вітамінних додатків, що містять аскорбінову кислоту)
    (Видавництво Львівської політехніки, 2015) Бойко, Тарас; Христина, Дух
    Проаналізовано структуру вимог до біологічно активних добавок відповідно до міжнародних нормативних документів; виконано їх порівняльний аналіз з національними вимогами. Показано, що вдосконалення чинного нормативного забезпечення щодо вимог безпеки біологічно активних добавок повинно ґрунтуватись на вимогах HACCP. Запропоновано визначати ризики як комбінацію втрат, оцінених через “втрату якості” схильних до небезпеки об’єктів, та вірогідності виникнення небезпеки, отриманої експертним оцінюванням ймовірності її виникнення. Зроблено висновок, що, ідентифікуючи на основі отриманих оцінок у продукті небезпечні чинники з найвищим ризиком, можна достовірно визначати критичні точки контролю і здійснювати відповідні коригувальні дії, а отже, підвищити ефективність системи НАССР. Проанализирована структура требований к биологически активным добавкам согласно международным нормативным документам; выполнен их сравнительный анализ с национальными требованиями. Показано, что совершенствование существующего нормативного обеспечения требований безопасности биологически активных добавок должно базироваться на требованиях HACCP. Предложено определять риски как комбинацию потерь, оцененных как “потеря качества” предрасположенных к опасности объектов, и достоверность возникновения опасности как экспертная оценка вероятности ее возникновения. Сделан вывод, что, идентифицируя на основе полученных оценок в продукте опасные факторы с наивысшим риском, можно достоверно определять критические точки контроля и соответствующие корректирующие действия, а следовательно, повысить эффективность системы НАССР. Biologically active additives (Dietary Supplements) - a special product that is used to correct the structure of human nutrition and to prevent certain diseases. One of the most common supplements are vitamin supplements. Their use is recommended in situation when the number of vitamin in the body is insufficient. That is why vitamin additives should be considered as an important products that require a responsible attitude to the evaluation of their quality characteristics. First of all it concerns safety hazard - risks. Organization that specifically created for standardization requirements for food products is the Codex Alimentarius Commission. The Commission acknowledges dietary supplements that contain vitamins and minerals as food, it is obvious that they should apply the requirements of ISO 22000: 2005. According to the standard, the concept of food safety means that food will not cause harm to the consumer when it is prepared and / or consumed in food according to its intended use. Food is characterized by the food chain, which is the sequence of stages and operations since primary production to consumption. Food Safety should be monitored at all stages of the food chain. Basic concept by which determined food safety is a food safety hazard. It is a biological, chemical or physical agent in food or a condition of product, potentially causing adverse health effects. Risk as combinations of likelihood of damage and the effects of the damage. Risk is a quantitative assessment of food safety hazard. In particular, in the context of food safety risk is determined as a function the likelihood of adverse health effects (eg, the probability of disease) and materiality consequences of such exposure (eg, disease severity). In turn, severity, such as can be determined indirectly through duration of lasting disability of the employee in the event of defeat this dangerous factor and the probability determined by the characteristics of the distribution of probability derived from statistical processing of disability cases for the period. For mentioned the size of the losses (primarily as a component of risk) assessment of the proposed so-called "quality loss". The concept requires explanation. Let facility in certain circumstances, can become a source of potential danger. If its quality as a set of properties that are responsible for security, goes to the “one”, the danger of such an object goes to zero and vice versa. Quality, as we know, can be estimated using the methodology of qualimetry using indicators of quality, which in our case will be safety indicators. The contribution of each indicator in the overall assessment of the factors traditionally expressed by weight coefficients. The risk can be determinated as a danger of loss quality, means deviation qualimetric assessment from “one”. Probability danger (the second component of risk) should be determined based on the prerequisite programme food safety, which is the basic conditions and activities necessary to maintain the desired environmental hygiene throughout the food chain. Separate prerequisite programme is specific in each field, depending on the segment of the food chain, which operates the organization and type of organization. For example, it may be: Good Agricultural Practices (GAP), Good Veterinary Practice (GVP), Good Manufacturing Practice (GMP), Good Hygiene Practices (GHP), Good Practice Primary Production (GPP), Good Distribution practice (GDP). The specified for certain products are operational prerequisite programme, containing identification and analysis of hazards that are significant to control their introduction to the food product. Identification, analysis and setting of values of probability in expert way involving, for example, the method of direct evaluation. As food safety depends on the presence of these dangerous factors at the time of consumption, and the hazards can appear on any stage of the food chain, for adequate control in each link of the food chain must have the specific values of all possible risks. Accordingly, the requirements ofHACCP should form the operational prerequisite programme identification and analysis of dangerous factors, which are essential to control the probability of introduction to food and to provide control measures and monitoring. Required to identify hazards in the product at high risk (assessment). And for each establish critical control points, critical limits, monitoring procedures and corrective actions.