Вимірювальна техніка та метрологія. – 2016. – Випуск 77

Permanent URI for this collectionhttps://ena.lpnu.ua/handle/ntb/39773

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, 2016. – Випуск 77. – 198 c. : іл.

Browse

Now showing 1 - 20 of 28

Антропогенна трансформація властивостей екотонів захисного типу на шляхах залізничного транспорту
(Видавництво Львівської політехніки, 2016) Обшта, Анатолій; Сорока, Ірина; Руда, Марія; Національний університет “Львівська політехніка”; Національний лісотехнічний університет України
Подано результати досліджень щодо формування екотонів захисного типу та створення інформаційно-аналітичної системи підтримки управлінських рішень для забезпечення рівня їх функціонування, який відповідає міжнародним стандартам, що регламентують сучасні вимоги до систем захисту довкілля. Представлены результаты исследований по формированию экотонов защитного типа и созданию информационно-аналитической системы поддержки управленческих решений для обеспечения уровня их функционирования, который соответствует международным стандартам, регламентирующим современные требования к системам защиты окружающей среды. The influence of rail transport on the environment creates many problems as it includes violation of the stability of natural landscapes transport infrastructure through the development of erosion and landslides; air pollution by exhaust gases; permanent increase in oil pollution of earth, lead, blowing products and shedding of bulk cargo (coal, ore, cement). Along with the benefits offered by the railway transport, there arise accute lssues of environmental safety during its use, which is caused by its negative and even destructive impacts on the environment. Sanitation methods provide for mandatory monitoring of the environment. The object of study is the quality of protective ecotones of the Lviv Railway. The forest shelterbelts, investigated in the railway sections Lviv – Sambir, Lviv – Ivano-Frankivsk, Lviv – Rava-Ruska, Lviv – Kovel, Lviv – Krasne, Lviv – Mostyska, Lviv – Stryi, Stryi – Mukachevo, and Ivano-Frankivsk – Chernivtsi, are mainly double-row ones (except natural forests growing along the railway lines) of 200 m in width on both sides of the track. The species composition of the stands is characterized by its diversity depending on forest site type. The trees are often top-drying, from the side of the railway tracks they have windfirm and dense crowns. The undergrowth is suppressed by snow drifts. The protective ecotones are characterized by the distribution of precipitation, soil moisture, and productivity of the adjacent agricultural lands. As a result, a kind of parademe system is formed along the Lviv Railway lines,consortium, that significantly differs from natural one due to overlapping ecological niches. This consortium has much in common with conserved (ecological) corridors because the integrated assessement shows increasing species diversity of agrosystem flora by 17 – 73%, entomofauna – by 27 – 62.5%, zoofauna – by a factor of 2.7 times. According to the field studies, we have classified the protective ecotones of the Lviv Railway by characteristics of profile, i.e. the structure and composition of plantations by their origin. Full-profile protective ecotones are plantations where the structure of shelterbelts (ecotones) can be clearly seen, they can be found in all sections of the Lviv Railway where the protective forest plantations were artificially created. Predominantly, they consist of one or, less common, three strips. Ecotone is formed at the boundary of two different anthropogenic tracts in a railway precinct. Across the study sections of the railway lines, only mixed stands were observed, no pure stands were found. A field study of ties between morphology and function of cumulative and ecosystem engineer; statistical methods investigated the potential protective effect of ecotones Lviv railway. The complex and differentiation characteristics of cumulative function of protective ecotones depends on the morphology and composition of forest communities –edificator. In the structure of vegetation in the consortium of protective ecotones, there is a significant amount of synanthropic and acclimatized species. Active processes are currently observed of human-induced changes in primary stands to form natural-anthropogenic stands in a wider array. The aggregate of protective ecotones at the Lviv Railway is functioning as a single system or forest reclamation complex that serves as the ecological framework where elements and subsystems interact providing a synergistic effect. Proceeding from the necessity of shifting to landscape-ecological principles of management and ensuring the maximum possible protective effect, the creation of a system of protective ecotones is one of the most innovative ways of ensuring ecosystem sustainability, in particular, enhancing their buffering capacity due to partial renewal of forest ecosystems as an integral component of natural landscape, which will provide for environmental safety on railway lines using only natural mechanisms of environmental protection. Method of investigation of environmental safety in railway transport is of great polyfunctional importance as this enables, on the basis of the landscape-ecological methods, to form consortiums of protective ecotones that will provide the maximum spatial-temporal efficacy.
Класифікація ризиків комунікацій під час надання освітніх послуг
(Видавництво Львівської політехніки, 2016) Бойко, Тарас; Сищук, Ольга; Національний університет “Львівська політехніка”
Проаналізовано суть терміна “ризик” та суміжних понять, запропоновано їх однозначне трактування. Розроблено класифікацію ризиків, які можуть супроводжувати навчальний процес на всіх його етапах. Встановлено основні причини виникнення ризиків. Охарактеризовано небажані чинники, втрати і властиві їм ризики, а також можливий спосіб оцінювання ризиків комунікації під час надання освітніх послуг. Проанализировано суть термина “риск” и смежных понятий, предложено их однозначную трактовку. Разработана классификация рисков, которые могут сопровождать учебный процесс на всех его этапах. Установлены основные причины возникновения рисков. Представлена характеристика нежелательных факторов, потерь и присущих им рисков, а также возможный способ оценки рисков коммуникации во время оказания образовательных услуг. To minimize the effect of unwanted factors and losses in the provision of educational services are important because they directly affect the level of training and their ability to carry out professional activities. Therefore, the investigation, analysis and classification of the losses and the risks involved in the learning process is an urgent task. In General, the risk is the estimated loss as a result of adverse factors that can accompany any production process and its participants, in particular the process of providing educational services. The value of the loss of information is characterized by uncertainty. And the possibility of loss of information associated with the reason, place, time and conditions of its occurrence, characterizing uncertainty. The General notion of risk is using to determine the size of the information uncertainty together with the uncertainty of its occurrence. Here risk communication is to evaluate the result of the negative impact of the loss of information caused by an undesirable factor, to achieve the purpose of communication. Evaluating loss of information possible to create the conditions for the effective management. Managing risk losses and to improve the quality of educational services. As a result of observation of the process of exchange of information was revealed six groups of undesirable factors, induced respectively by the two types of problem situations that can accompany the process of communication. We will distinguish between two kinds of problem situations, the first of which concerns the participants in the exchange of information, and the second concerns the process of information exchange between them. Overall, the above problem situations lead to a theoretically unlimited number of undesirable factors. However, in the process of researches it is established that the list of losses that are the result of adverse effects of unwanted factors is limited, and therefore is limited and the amount of risk communications. The results of the analysis of all possible communications were summarized only five of the typical losses and their risks: the risk of transportation; the risk of apperception; didactic risk; the risk of misinformation and the risk assessment. Describe more undesirable factors and the risks generated by them. 1. Undesirable factors associated with the essence of information arise due to the fact that the received listener information is essentially one that does not contain training material or the material is inaccessible to perception; entail these risks: the risk of apperception, teaching risk, the risk of misinformation. 2. Undesirable factors associated with the personality and the professional level of teacher, which is the information provider, in particular with the state of his mental and physical health, individual traits, temperament, oratory skills, professional skills, qualifications, knowledge, teaching skills and teaching abilities, as well as the motivation of these abilities to use in the process of delivering information to the listener; entail these risks administrative risk; risk of misinformation; risk assessment. 3 Undesirable factors associated with the personality of the listener who is a consumer (receiver) information, in particular, individual traits of character as psychological and physical health, motivation, training skills, advanced training; entail these risks: the risk of apperception; risk of misinformation; risk assessment. 4 Undesirable factors associated with language, which is the main communication tool and information display. As to convey to the listener information, it is crucial that there is a need to allocate a separate group unwanted factors that can arise through language barriers or barriers of the culture of speech; entail these risks administrative risk; risk of misinformation; risk assessment. 5 Undesirable factors associated with non-verbal media, which are not the main means of communication, but significantly affect the communication process. Also in this group are undesirable factors, which can occur because of related actions, deeds or circumstances accompanying the communication parties; entail these risks: the risk of apperception; didactic risk; risk evaluation.6 Undesirable factors associated with the means of delivering information from the "source" to "receiver", which are objective. Basically there is a question of the technical means by which information make it easier to understand, illustrated visually or by voice; entail such risks: the risk of transportation; the risk of misinformation. All except the last listed of the impact of undesirable factors lead to losses of educational information. The latest factor – for qualifying losses that may occur in the appraisal process level of the student. As any process of providing educational services contain a certification component, and an incorrect assessment of the level of assimilation of information by the listener makes impossible its logical conclusion, such loss must also be taken into account.
Дослідження термометричного матеріалу HF1-хErxNiSn
(Видавництво Львівської політехніки, 2016) Крайовський, Володимир; Національний університет “Львівська політехніка”
Досліджено енергетичні, кінетичні та магнітні характеристики термометричного матеріалу Hf1-xErxNiSn у діапазонах T = 80÷400 K, x=0÷0.10 за напруженості магнітного поля H £10 кГс. Показано, що характеристики Hf1-xErxNiSn чутливі до зміни температури і він може бути основою для виготовлення чутливих елементів термоперетворювачів. Исследованы энергетические, кинетические и магнитные характеристики термометрического материала Hf1-xErxNiSn в диапазонах: T = 80÷400 K, x=0÷0.10 при напряженности магнитного поля H £ 10 кГс. Показано, что характеристики Hf1-xErxNiSn чувствительны к изменениям температуры и он может быть основой для изготовления чувствительных элементов термопреобразователей. The electron energy state, magnetic and transport characteristics of of thermometric materials Hf1-xErxNiSn were investigated in the T = 80÷400 K temperature range and at charge carriers concentration from x=01÷0.10 and H £ 10 kGs. The material Hf1-xErxNiSn is sensitive to the temperature change and could be used as the basis for the sensitive thermoelectric devices. We investigated the crystal structure, electron density of states (DOS) and the kinetic and energy characteristics of n-HfNiSn heavily doped with the Er impurity. Samples were synthesized at the laboratory of the Institute of Physical Chemistry, Vienna University. The Hf1-xErxNiSn crystal-lattice periods were determined by X-ray analysis with the use of the Full-prof software. We employed a data array obtained by the powder method using a Guinier-Huber image plate system. The chemical and phase compositions of the samples were determined using a Ziess Supra 55VP scanning electron microscope and an EMPA energy dispersive X-ray analyzer. The electronic structure was calculated by the Korringa–Kohn–Rostoker (KKR) technique in the coherent potential approximation (CPA) and local density approximation (LDA), as well as the full-potential linearized plane wave (FP-LAPW) method within density functional theory (DFT). In the calculations, we used experimental values of the lattice constant on a k grid 10×10×10 in size and the Moruzzi–Janak–Williams exchange-correlation potential parametrization. The width of the contoured energy window was 16 eV. The number of energy values for DOS calculations was 1000. To predict the behavior of the Fermi level, band gap, and electrokinetic characteristics of n-HfNiSn doped with Eratoms, the electron density distribution (DOS) was calculated. The calculated results pretending to be adequate to experimental studies should account for complete information on the semiconductor’s crystalline structure. To obtain more accurate results, we calculated the DOS for almost all possible cases of the mutual substitution of atoms at sites of the HfNiSn unit cell. Shows the result most consistent with experimental data. It was found that the disordered structure (Hf1-xNix)NiSn, x = 0.01, of the HfNiSn compound is most probable. We note that the same result was obtained from structural studies of HfNiSn. The partial (to 1 at %) substitution of Hf atoms with Ni atoms generates donor-type structural defects in the crystal, and the Fermi level is in the band gap which becomes narrower. It was also found that the minimum in the dependence of variations in the DOS at the Fermi level (DOSF(x)) for the disordered structure (Hf1-xNix)NiSn of the HfNiSn compound corresponds to the (Hf0.99Ni0.01)NiSn composition. In this semiconductor model, the Fermi level is in the band gap which is εg ≈ 282 meV. The same question arises when analyzing the behavior of the dependences (x) and (x) in Hf1-xErxNiSn. For example, the (x) variation in the concentration range 0.02 ≤ x ≤ 0.10 shows that the modulation amplitude of the continuous energy bands of Hf1-xErxNiSn HDCSs increases. Indeed, the activation energies (x) increase from (x = 0.05) = 38.3 meV to (x) (x = 0.07) = 59.2 meV. As we already noted, such behavior is possible only when compensating electrons appear in the p-type semiconductor due to the ionization of donors whose appearance was not initially assumed. In Hf1-xErxNiSn samples, x > 0.05, the decrease in (x) indicates a decrease in the modulation amplitude of the continuous energy bands, which is possible only when the degree of compensation of Hf1-xErxNiSn decreases due to a decrease or termination of the generation of donor-type structural defects. Thus, the initial assumption that n-ZrNiSn doping with Er atoms by substituting Hf atoms is accompanied by the generation of only donor-type structural defects in the crystal does not allow consistent explanation of the behavior of the energy characteristics of Hf1-xErxNiSn HDCS. The variations in the activation energy of hopping conduction (x) and the modulation amplitude of the continuous energy bands (x) unambiguously prove the existence of a donor source in Hf1-xErxNiSn. Further, we will identify the possible mechanism for the appearance of donors. The series of studies on the crystalline structure, energy spectrum, and electro-kinetic parameters of the n-HfNiSn intermetallic semiconductor heavily doped with the Er impurity allowed determination of the variation in the degree of compensation of the semiconductor due to the generation of both structural defects of donor nature during the substitution of Hf atoms with Er atoms and defects of donor nature during the partial substitution of Ni sites with Snatoms. The n-HfNiSn crystalline structure is disordered, and the Hf site can be occupied by Ni to ~1 at %, which generates structural defects of donor nature in the semiconductor and explains the mechanism of its “a priori doping with donors”. The mechanism of the degree of compensation of the semiconductor as the result of the crystal structure transformation during doping, leading to the generation of structural defects of donor nature was established. The results of the electronic structure calculation are in agreement with experimental data and the Hf1-xErxNiSn semiconductor is a promising thermoelectric material. The results are discussed in the framework of the heavily doped and compensated semiconductor model by Shklovsky–Efros.
Удосконалення структурних методів коригування адитивних похибок калібраторів напруги постійного струму
(Видавництво Львівської політехніки, 2016) Матвіїв, Роман; Національний університет “Львівська політехніка”
Вдосконалено метод коригування адитивних складових похибок на основі комутаційного інвертування в калібраторах напруги постійного струму з елементами аналогової пам’яті комутаційних двополярних сигналів. Спроектовано структурну схему і принципові схеми окремих вузлів калібратора напруги з автоматичним коригуванням адитивних похибок і проведено їх дослідження. Усовершенствован метод коррекции аддитивных составляющих погрешности на основе коммутационного инвертирования в калибраторах напряжения постоянного тока с элементами аналоговой памяти коммутационных двуполярных сигналов. Спроектирована структурная схема и принципиальные схемы отдельных узлов калибратора напряжения с автоматической коррекцией аддитивных погрешностей и проведены их исследования. In normal operating conditions the error correction is usually conducted shifting the transformation function of DC voltage calibrators by introducing a corrective quantity equal in value and opposite in sign to additive error. This additive error correction is performed in manual and automatic modes. Additive errors of DC voltage calibrators are mainly caused by zero bias of the transformation function of analog electronic components in electronic circuit and voltage drop in communication lines between different circuit nodes. The additive errors caused by the operational amplifier equivalent offset voltage, are added to the output voltage of DC voltage calibrator and converted into multiplicative errors through the use of code-control dividers. Additive errors of the output scale converters of DC voltage calibrators cause additive offset of output voltage. In addition, they can also occur during the passage of supply current of different device units through the common communication lines between them. The structural and technological methods are used to reduce these errors. The review of additive error adjusting methods by means of inverting switching is conducted. Therefore, to use the additive error adjusting methods in DC voltage calibrator it is necessary to conduct their research and improvement. The method of additive error adjusting based by means of inverting switching DC voltage calibrator with analog memory elements of switching bipolar signals is improved. The block diagram of the DC voltage calibrator with double inversion is analyzed. The graphics dependences of additive error for different values of frequency clock generator, time delay and transmission rate of code-controlled divider are considered. The dependences of output voltage error value from the output signals delay formation are also investigated. Based on the analysis shows that the main drawback to switching-inverting method is the effect of forming precision pulse control keys and signals delay formation arising from the lack of speed switching transients and key operational amplifiers and code-controlled divider. To eliminate the influence of outputs transients proposed output elements of operational amplifier are stored in analog memory. A structural diagram output of DC voltage calibrator with analog memory elements. A description of scheme and given equation output voltage. From these equations shows that the resulting delay from switching the input and output signals create multiplicative error on frequency clock generator and time value delay. Under this factor of multiplicative error can be adjusted change in transmission kodecontrolled divider for a clock frequency generator of value. Improved principle scheme of separate units DC voltage calibrator with automatic errors correction and conducted its investigation and presented graphic dependences of the output voltage changes of the combiner. Analysis of graphical dependences shows that amplitude of the variable component of combiner output depends on the time constant memory elements and adder. When τ = 18 ms value variable component equal to 0.25 mV at a clock generator frequency of 1000 Hz and 0.5 mV at a frequency of 500 Hz. To reduce the variable component of the voltage at the output combiner is applied passive filter on condenser C3 and active at operational amplifier DA2. Accordingly, for the variable component value less than 1 mVmust apply suppression filter coefficient K = 47 dB at a clock generator frequency of 1000 Hz and K = 54 dB at a frequency of 500Hz. Computer research determined that the applied filter reduces a variable component not exceed to 1 mV. The proposed method of component additive error correction DC voltage calibrator from inverting switching voltage source model and output amplifier with switching signal analog memory elements output amplifier completely component additive errors corrects and improves dynamic performance DC voltage calibrator.
Оптимізований метод вимірювання позитронних анігіляційних спектрів у наноматеріалах з розвиненою поруватістю для сенсорних застосувань
(Видавництво Львівської політехніки, 2016) Клим, Галина; Костів, Юрій; Чалий, Дмитро; Івануса, Андрій; Ткачук, Тарас; Національний університет “Львівська політехніка”; Львівський державний університет безпеки життєдіяльності
Запропоновано та використано оптимізований за апаратною складністю метод вимірювання позитронних анігіляційних спектрів для дослідження вологочутливої кераміки MgО-Al2O3 з розвиненою нанопоруватістю. Показано, що в разі розкладу спектрів на чотири компоненти вдається оцінити розміри нанопор за моделлю Тао-Ельдрупа та вивчити процеси, які відбуваються в них. Встановлено, що частка нанопор радіусом ~1,5 нм на порядок перевищує частку пор з радіусом ~ 0,3 нм, в яких також відбувається анігіляція ортопозитронію у адсорбованій воді. Предложен и использован оптимизированный за аппаратной сложностью метод измерения позитронных аннигиляционных спектров для исследования влагочувствительной керамики MgО-Al2O3 с развитой нанопористостью. Показано, что при разложении спектров на четыре компоненты удается оценить размеры нанопор по модели Тао-Ельдрупа и изучить процессы, происходящие в них. Установлено, что доля нанопор радиусом ~ 1,5 нм на порядок превышает долю пор с радиусом ~ 0,3 нм, в которых также происходит аннигиляция ортопозитрония в адсорбированной влаге. An optimized by hardware complexity method for measuring of positron annihilation lifetime spectra was proposed and used to investigation of humidity-sensitive MgO-Al2O3 ceramics with advanced nanoporosity. Positron-positronium annihilation spectrum were analyzed using four-component fitting procedures. It is shown that this technique can be used to investigation of nanopores transformation in humidity-sensitive MgO-Al2O3 ceramics as porosimetry method. It is shown that Tao-Eldrup model can be used for study of size of nanopores smaller then 1,5 nm. It has been shown that for MgO-Al2O3 ceramics two positron annihilation channels should be considered – the positron trapping with shortest t1 and middle t2 lifetimes and ortho-positronium decaying with the longest t3 and t4 lifetimes, these channels being independent ones. Assuming the two-state positron trapping model for spinel ceramics, four components in the fit of the experimental spectra can be associated with the microstructure peculiarities of the spinel. This microstructure exhibits characteristic octahedral and tetrahedral cation vacancies (t1, I1), positron trapping extended defects located near grain boundaries and positron traps in the free-volume entities (t2, I2). Ortho-positronium decay in nanopores of ceramics is described by t3, I3 and t4, I4. Within the formalism of this model, the open volume entities free of the electron density are treated as defects, while hypothetical structure without these entities is treated as the defect-free bulk. It is established that the third component of lifetime spectra gives information about ortho-positronium decaying in nanopores with water and fourth component reflects ortho-positronium trapping in free-water volume of nanopores. It is established that in inner structure ceramic materials there are two types of nanopores. The intensity of the third component of the spectrum increases in water-filled samples, while the intensity of four components – decreases. The most significant changes caused by water adsorption processes are observed in largest nanopores with radius of ~1,7 nm. Reducing the value of the lifetime t4 after drying of ceramics can be due to the formation of thin layers of water molecules surrounding the large pores. The lifetime t3 decreases after water vapor of ceramics with a gradual increase in drying and intensity I3 grows, indicating annihilation of ortho-positronium in water-filled nanopores. The presence of water in the nanopores of smaller radius of ~0.3 nm after drying reflects increasing of intensity I3 and a slight decreasing of lifetime t3. It is noted that ortho-positronium lifetime ~1,7 ns reflects the annihilation in the water “bubbles” with radius of ~0.3 nm.
Розумні вимірювальні засоби для кіберфізичних систем
(Видавництво Львівської політехніки, 2016) Микийчук, Микола; Стадник, Богдан; Яцишин, Святослав; Луцик, Ярослав; Національний університет “Львівська політехніка”
Праця спрямована на розвиток кіберфізичних систем, які стають ключовим фактором повсякденного життя, а розумні вимірювальні прилади вважають невід’ємним компонентом цієї системи. Розглядається верифікація метрологічних підсистем за параметрами, що визначають керованість обладнання та процесів, розробленням, впровадженням та реалізацією конкретних метрологічних методів та інструментів, які успішно описуються термінами “апаратна підтримка, основне і проміжне метрологічне програмне забезпечення”. Работа направлена на развитие киберфизических систем, которые становятся ключевым фактором повседневной жизни, а умные измерительные приборы считаются неотъемлемым компонентом этой системы. Рассматривается верификация метрологических подсистем по параметрам, определяющим управляемость оборудования и процессов, путем разработки, внедрения и реализации конкретных метрологических методов и инструментов, которые успешно описываются терминами “аппаратная поддержка, основное и промежуточное метрологическое программное обеспечение”. Smart measuring instruments are the prerequisite for CPS design as they constitute the essential units of informationmeasuring subsystems. There is a set of smart measurement instruments which is divided into the following subsets: smart sensors, smart transducers, their grids etc. that can be joined together in modern wireless sensor networks. The emerging field of cheap and easily deployed sensors offers an unprecedented opportunity for a wide spectrum of various applications. When combined, they offer numerous advantages over traditional networks. These include a large-scale flexible architecture, high-resolution data, and application-adaptive mechanisms as well as a row of metrological specific features and performance (self-check, self-validation, self-verification, self-calibration, self-adjustment). Milestones in everyday work aiming to ensure reliable wireless sensors networks operation lie in the direction of functional and probabilistic verifications. We provide the software and middleware development aiming to reach predetermined behavior. The easiest way to achieve this may be demonstrated on the example of widespread wireless fire detector networks. They are characterized by a number of special algorithms directed on as fast as possible and accurate triggering and actuating the automation of higher level. So, it becomes necessary to research and implement the original operation algorithms for fire sensors and also check algorithms for periodic real-time software examination. Considering their structural complexity (presence of smoke and heat sensitive elements, various principles of elaboration of the received signals, their drift of characteristics, and pollution of translucent elements, etc.) the development of such algorithms is a daunting task. Herein, human life may be the price for a bug. Equally important seems to be probabilistic verification that is to boost the probability of reaching wireless sensors network declared goals (estimation of their chances being achieved). Each network consists structurally of a large number (up to 103) of nodes which are individual sensors able to radio communicate with one or several neighboring units. The most common wireless sensors network is the fire alarm sensors network each branch of which has up to 26 sensors which was caused by limiting the length of microcontroller register. Topology of every network may differ: star, cluster tree, mesh, up to advanced multi-hop mesh network. Propagation technique between hops of network can be routing or flooding. Nowadays, problem arises to adapt traditional network topologies to contemporary communicating conditions. If a centralized architecture is used in a sensor network and the central node fails, then the entire network will collapse, however the reliability of sensor network can be increased by using distributed control architecture. Distributed control is used in such networks for the following reasons: sensor nodes are prone to failure; for better collection of data; to provide nodes with backup in case of the central node failure; resources have to be self -organized. Aiming at the substantial development of Cyber-Physical systems, which are becoming a key element of everyday life,the smart measuring instruments are considered below as an indispensable part of entire systems. Verification of the metrological subsystems for parameters determining the controlled equipment and processes through the development,implementation and realization of specific metrology and standardization methods, instruments, that is successfully described by the terms “metrological hardware, software, and middleware”. Smart sensors are supplied with digital information transmissive means by equipping them with built-in digital controllers to match the universal network interface or by combining technology of analogue and digital transmission in a single measuring channel. According to the structure all smart sensors are divided into 4 groups: sensors of centralized and decentralized types, as well as sensors with digital and analogue buses. According to correction methods the analogue interfaces with smart sensors are divided into the groups: with manual error correction, with auto correction of errors in analogue-digital form, and with digital correction of errors. Specific measurement consists in evaluating MIs performance reliability, trueness, and other metrological properties, due to the quality of a certain kind of metrological software, or the software linked to metrological features of MIs. MI software metrological verification raises the problem of appropriate methods choice of software and middleware assessing, testing, and certifying. The metrological validation must result in confirmation or discarding of the studied ware following the requirements indicated in normative documents. Procedures and methods of checking software, and determining its disadvantages are considered below. Software study includes first of all the fulfilling the procedures of inambiguity ensuring the operating functions for generated data. Selection of the procedures is determined by regulation requirements, as well as by the software developer or the user’s desires to confirm its compliance with the target specification.
Аналіз граничних умов працездатності вимірювальних перетворювачів імітансу на базі операційних підсилювачів
(Видавництво Львівської політехніки, 2016) Івах, Роман; Хома, Володимир; Хома, Юрій; Питель, Іван; Національний університет “Львівська політехніка”
Показано місце та роль активних вимірювальних перетворювачів імітанс-напруга у структурі частотного аналізатора. Проаналізовано фактори, які обмежують працездатність активних вимірювальних перетворювачів. Наведено формалізовані моделі цих перетворювачів та на їх основі встановлено граничні умови, пов’язані з їх стійкістю. Показано место и роль активных измерительных преобразователей иммитанс-напряжение в структуре частотного анализатора. Проанализированы факторы, которые ограничивают работоспособность активных измерительных преобразователей. Приведены формализованные модели этих преобразователей и на их основе установлены предельные условия, связанные с их устойчивостью. Development of specialized portable measurement tools for impedance spectroscopy is quite challenging and up-to-date technical task. Portable impedance analyzers are required to satisfy certain criteria among which the most important are the following: stability of metrological characteristics of measurement channel over a wide frequency range, high dynamics, fast frequency sweep and the probe signal with appropriate step as well as high resolution of impedance/admittance measurement results. Autobalancing circuits are widely used in impedance analyzers design. However, their applications is followed by some problems related to operation stability caused by global feedback loop. The aim of the paper is to study the stability of the active measurements converter based on autobalancing circuits as well as determining their operation limits. The article shows the place and role of active measuring converters immitance-voltage in the structure of the frequency analyzer. Formal models of active converters were used to analyses operational limits related to system stability. The main results of research can be summarized as following: – To determine operating frequency range of the autobalancing circuit can successfully convert impedance to voltage, following rule have been formulated. The upper limit of the frequency range should be taken at least ten times smaller than operational amplifier bandwidth. The lower limit is formally unlimited. – Circuit operational limits related to system stability depends on relation of operational amplifier bandwidth to closedloop knee frequency as well as relation of closed-loop knee frequency to operational circuit time constant (product of reference resistor to input capacitance). – The system is considered to be operating at normal conditions if relation of operational amplifier output resistance to reference resistance is equal or smaller then one. If the ratio excides this threshold, then measurement circuit will lose amplification properties at high frequency..
Застосування методу серій для дослідження взаємної кореляції спостережень
(Видавництво Львівської політехніки, 2016) Дорожовець, Михайло; Никипанчук, Олена; Національний університет “Львівська політехніка”
Запропоновано метод обчислення автокореляції, а також ефективної кількості спостережень. Для генерування корельованих спостережень використовується метод рухомого середнього. За допомогою методу серій можливе спрощене обчислення ефективної кількості спостережень для визначення стандартної непевності середнього значення корельованих спостережень. Предложен метод вычисления автокорреляции, а также эффективного числа наблюдений. Для генерирования коррелированных наблюдений используется метод подвижного среднего. С помощью метода серий возможно упрощенное вычисление эффективного числа наблюдений для определения стандартной неопределенности среднего значения коррелированных наблюдений. When processing the results of measurements big role important presence of correlation values. To find the standard uncertainty need to know the effective number of uncorrelated observations. No correlation can consider could lead to incorrect evaluation of the standard uncertainty of the mean. Not always known autocorrelation function monitoring, and evaluation of the autocorrelation function on observations characterized by low accuracy, which can lead to incorrect finding effective number. There are indirect methods of evaluating the impact assessment on observations correlation standard deviation. This method is recorded sample of N divided into k sub-samples (groups) up to n samples each (N = n · k). Each subsample are partial mean and variance estimation, and find the settings for the entire sample. Then compare the ratio of the variance between groups and within the group. Using the F distribution at a significance level α determined whether the observations are correlated or not. These methods are quite complex and require significant additional computing. The purpose of research is to study simple method of testing autocorrelation and consideration in calculating the Neff. The proposed method is based on calculating the number of series. Series is a sequence of observed values equal before which or after which the values observed are another category or no supervision at all. Set the number of series or observation results are correlated or not. To determine whether correlated observations required to determine the median of the sample and calculate the number of deviations from the median values. Research performed by theMonte Carlo. For research use two types of observations: first – with uncorrelated observations, the second – generated correlated observations, including the method ofmoving average. To find the index of correlation function used exponential autocorrelation function. An effective dependence theoretical number and effective number determined by the method episodes from different bias moving average on a constant number of observations. Based on these studies show that increasing the number of observations (N> 50) to simplify the calculation of the possible number of effective using the method of series. At least 50 the number of observations can be effective calculating numbers with a small biasmoving average.To investigate the cross-correlation of observations of the method is appropriate series and simplifies the calculation of the standard uncertainty.
Дослідження електричної та математичної моделі контролю якості овочів
(Видавництво Львівської політехніки, 2016) Мідик, Ігор; Чабан, Олеся; Національний університет “Львівська політехніка”; Львівський національний медичний університет імені Данила Галицького
Складено електричну та математичну модель контролю якості об’єктів неелектричної природи, враховуючи відомі сьогодні прототипи та результати проведених експериментальних досліджень зміни активної та реактивної складових провідності (адмітансу) в частотному діапазоні тестового сигналу. Проведено математичне моделювання складових адмітансу в разі зміни ємності приелектродного шару, опору та ємності об’єкта неелектричної природи у частотному діапазоні тестового сигналу. Опрацьовано отримані результати зміни активної та реактивної складових провідності, подано рекомендації щодо оптимального частотного діапазону проведення вимірювань та особливостей конструктивних елементів електричної моделі контролю якості об’єктів неелектричної природи. Составлено электрическую и математическую модели контроля качества объектов неэлектрической природы, учитывая известные сегодня прототипы и результаты проведенных экспериментальных исследований изменения активной и реактивной составляющих проводимости (адмитансу) в частотном диапазоне тестового сигнала. Проведено математическое моделирование составляющих адмитанса при изменениях емкости приелектродного слоя, сопротивления и емкости объекта неэлектрической природы в частотном диапазоне тестового сигнала. Обработано полученные результаты изменения активной и реактивной составляющих проводимости и даны рекомендации относительно оптимального частотного диапазона проведения измерений и особенностей конструктивных элементов электрической модели контроля качества объектов неэлектрической природы. Operational control of quality vegetables can be made using the method immitance control their electrical parameters.Vegetables – are objects of non-electric nature, and their juices – this electrolyte solutions, where there are free charged particles – ions, and it immitance method is based on measuring the electrical conductivity control objects. Therefore, research is relevant electrical parameters vegetable juices as well as development of electric and mathematical models immitance contact transducer. The object of the research is the process of measuring electrical parameters of objects of non-electrical nature. The study examined the features are measuring electrical parameters of the objects of nature electic primary contact transducers. The aim of the research is to identify the influence of parameters of contact transducers for measuring electrical parameters results electic nature objects in a frequency range test signal. Main tasks: – Make electric model quality control facilities electic nature; taking into account known today prototypes; – Make a mathematical model of quality control facilities electic nature; – Assess the impact of the model parameters (resistance and capacitance facility and capacity electrode layer) on the results of measurements of electrical parameters electic nature objects in a frequency range test signal. To study the electrical parameters of vegetable juice prepared generalized electrical equivalent circuit system “sensormeasuring tool”. Based on the equivalent circuit constructed system “sensor-measuring means” formed mathematical model of the transformer primary object of control. Informative electrical parameters are immitance components (active and reactive component) primary converter with vegetable juice (non-electric research object nature). Make up electrical and mathematical model of quality control objects non-electrical nature, taking into account known today prototypes and the results of experimental studies of changes active and reactive components of the conductivity (admittance) in the frequency range test signal. Using the experimental results of change of active and reactive components of the conductivity (admittance) using Solve Block in the software package MathCad Prime 3.1, values obtained resistance and capacitance object electic nature and capacity electrode layer in a frequency range test signal. Done mathematical modelling of admittance components with changes capacitance of electrode layer, resistance and capacitance of object non-electrical nature in a frequency range test signal. Processed obtained results of change of active and reactive components of the conductivity and provides guidance on the optimal frequency range of measurement and features of structural elements of the electrical model quality control objects non-electrical nature. The results of mathematical modeling components admittance was concluded that with increasing frequency electrode layer capacitance Cn frequency from which the active component is independent frequency decreases.And for independence measurement result object nature electic resistance Rx = 46 ohms and a capacity Cx = 1500 pkF (eg Carrot juice) at lower frequencies necessary to increase the capacity electrode layer, using a sensor with a greater area of the electrodes.Changing the capacity control object Cx does not affect the value immitance (this follows from the analysis of the expression of the active component of impedance as Cn >> Cx). Frequency from which reactive component is practically constant, slightly increases with increasing facility capacity control Cx. With the growing resistance of the control object Rx = 20, 40, 60, 80, 100 ohms (this range of resistance values corresponding to different vegetable juices) curves active component of impedance shifted downward by the value of active component of impedance and left in frequency, that frequency, from which the active component is independent frequency decreases. Therefore, for the independence of the measurement result object electic nature with less resistance required measurements at higher frequencies. However, with increasing resistance Rx frequency control facility from which the reactive component is practically constant, unchanged.
Аналіз похибки вимірювання кута напряму на ціль розподіленою системою звукової артилерійської розвідки
(Видавництво Львівської політехніки, 2016) Трембач, Богдан; Кочан, Роман; Національний університет “Львівська політехніка”
Проаналізовано похибку визначення кута на ціль у системі артилерійської звукової розвідки. Досліджено обчислювальну складність формули для визначення відстані між звукоприймачами. Проаналізовано основні джерела похибки під час визначення кута напряму на ціль. Показано залежності складових похибки визначення кута на ціль. Проанализирована погрешность определения угла на цель в системе артиллерийской звуковой разведки. Исследована вычислительная сложность формулы для определения расстояния между звукоприемниками. Проанализированы основные источники погрешности при определении угла направления на цель. Показано зависимости составляющих погрешности определения угла на цель. The analysis determining the angle error on the target system artillery sound intelligence. Studied computational complexity of the formula for determining the distance between the sound receivers. The basic source of error in determining the direction angle to the target. Showing error components depending determine the angle to the target. Sound is a type of artillery reconnaissance and combat support artillery units [1], which uses acoustic stereo to determine the direction to the target. Means sound intelligence forces Ukraine is sound-metric-type filling station AKZ-7. However, their condition technical readiness can not effectively carry out the sound of artillery reconnaissanc. In [4] proposed a distributed sound system of automatic artillery reconnaissance using a plurality of independent sound receivers located on the ground and combined with wireless network using cellular channels. Sound acoustic receivers provide environmental monitoring and the detection of sound of a shot or pass to break the sound server system time and their geographic coordinates. The server system provides data aggregation sound receivers and presenting the results of the system to authorized users. The aim of this work is to investigate the accuracy of measurement of the angle to the target in the implementation of systems based on advanced cellular terminals (smartphones). In [5] analyzed the errors of determining the angle to the target system artillery sound intelligence.Analiz showed that the computational complexity of the formula used to estimate the error of the system is unnecessarily high. Analysis of distance between two geographical points that are scattered over a distance of 3 km (expected maximum allowable distance between the sound receivers, they hear one goal) showed that it corresponds exactly service Google Maps. Function arguments are: the distance between the sound receivers during the fixation of sounds goals sound receivers and the speed of sound in air. Error of these variables will determine the angle error of the target. The dependence on the angle determining the distance between the target sound audio receivers distributed system intelligence based artillery systems provider. It tested a new method of determining the distance by geographical coordinates and compared the results with the service Google Maps. Established that the accuracy of the distance, the new method is not inferior to existing ones. This allows you to determine the distance to within 1 meter. The greatest influence on the resulting error gives a measure of time. Therefore, a further step to improve the determination of the angle of the target is to reduce the error determination time.
Нові методи теплової томографії, а також фільтрації тепловізійних зображень
(Видавництво Львівської політехніки, 2016) Мельник, Сергій; Петріченко, Геннадій; Тулузов, Ігор; ІРЕ ім. А. Я. Усікова НАН України; ТОВ НВФ “Харків-Прилад”; Харківський регіональний центр інвестицій
Запропоновано два нові методи теплової томографії, основані на оригінальних методиках нагрівання та алгоритмах розв’язання оберненої задачі теплопровідності в об’єкті контроля. Додатково запропоновано три методи оброблення тепловізійних зображень, що ґрунтуються на урахуванні динаміки термографічного зображення та дають змогу відфільтрувати артефакти, пов’язані із неоднорідністю коефіцієнта випромінювання поверхні, значно збільшують кількість віртуальних пікселів та якість зображення, дають змогу максимально повно використати апріорну інформацію для розв’язання некоректних обернених задач реконструкції. Наведено приклади застосування цих методів до задачі контролю каналів охолодження у лопатках турбін. Предложены два новых метода тепловой томографии, основанных на оригинальных методиках нагрева и алгоритмах решения обратной задачи теплопроводности в объекте контроля. Дополнительно предложены три метода обработки тепловизионных изображений, которые основаны на учете динамики термографического изображения и позволяют отфильтровать артефакты, связанные с неоднородностью коэффициента излучения поверхности, значительно увеличивают количество виртуальных точек и качество изображения, позволяют максимально полно использовать априорную информацию при решении некорректных обратных задач реконструкции. Приведены примеры применения этих методов к задаче контроля каналов охлаждения в лопатках турбин. Two new thermal imaging methods, based on the original methods of heating and algorithms for solving the inverse problem of heat conduction in the test object. In addition, proposed three methods of thermal imaging, which are based on the account of the dynamics of thermographic images and allows you to filter artifacts related to the heterogeneity of the surface emissivity, significantly increase the number of virtual pixels and image quality, allows maximum use of a priori information in the solution of ill-posed inverse problems of reconstruction. Examples of application of these methods to the problem of the cooling channels in turbine blades control. The projection dynamic thermal tomography (PDTT) method is applicable for control of objects with irregular internal structure. It allows reliably detecting the foreign inclusion-type defects and controlling with high accuracy the geometric parameters of the internal structure of objects. This method is designed for using modern thermal imager with a standard set of parameters and does not require expensive additional equipment. Preliminary numerical analysis of capabilities of the proposed method for specific objects and the parameters of expected defects is possible, indicating the requirements to the parameters of thermal imager and heating. The PDTT method is superior in terms of information value to all alternative DTT methods and can also replace a number of more expensive control procedures using other methods (ultrasonic, x-ray, SHF). The generally accepted parameters of evaluating the quality of cooling turbine blades are missing. A wide range of sizes and theirs cooling mechanisms significantly complicate the use of such parameters as absolute values. We propose to use a universal relative parameter. It corresponds to the virtual heat transfer coefficient at a predetermined depth of the metal layer. It illustrates the possible use of this parameter for various methods of thermal control. It is shown that an integrated approach to the construction of the control system and the integration of different modes of cooling can significantly reduce the uncertainty of the quality of the cooling parameter. He is a local and could eventually be used to evaluate the residual life of the blade. In case of random nature of heating the measured thermal emission flow depends not only on the real surface temperature, but also on its emissivity factor. Unlike the known DTT methods, the filtration of artifacts requires taking account of the dynamics of the whole process. Such processing is performed in each pixel of the thermal image and the dynamics of measurements in adjacent pixels is also taken into account. The accuracy of the filtration is determined both by the number of adjacent pixels taken into account and the completeness of the obtained measurement information. The problems encountered when observing objects, whose dimensions do not exceed several pixels of the matrix of recorders. It is shown that the motion of the object relative to the matrix, and the use of multiple consecutive frames can significantly improve the fidelity of the shape and true size of the object. This measurement information can be represented as integrals along the trajectories on a three dimensional lattice of space-time pixels. The reconstructions of а heterogeneity function of pixels through the use of the controlled motion of the test object and methods of computer tomography. The possibility of determining the relative velocity of the object in each of the frames using the "blind" method. The algorithm of reconstruction of images with large non-uniform increment, as in passive, and when they are managed relative motion. An algorithmic approach to solving inverse problems of reconstruction of the structure of the scattering medium can significantly improve its informativeness in cases where the lack of prior information and a high noise level does not allow to use standard approaches. Thus, unlike statistical processing methods, constructing a set of hypotheses is not required. The unknown parameters of the processing procedure can be obtained using the "blind method" in the reconstruction process. This automatically eliminates the possible redundancy of model. The choice of language to describe the array of input data and the search algorithm of the model optimal parameters is determined not by the features of the device and the object of observation, but by the expected view of the final presentation of the results. The described technique is universal and can be used for solving different tasks of reconstruction as a whole, and in any intermediate signal processing.
Дослідження діелектричних властивостей речовин у діапазоні радіочастот
(Видавництво Львівської політехніки, 2016) Горват, Андрій; Молнар, Олександр; Мінькович, Віктор; Ужгородcький національний університет
Описано автоматизовану систему, яка дає змогу досліджувати діелектричну проникність у діапазоні частот 50 кГц − 50 МГц генераторно-резонансним методом з одночасним використанням принципів періодичного порівняння та заміщення. Описана автоматизированная система, которая позволяет исследовать диэлектрическую проницаемость на частотах 50 кГц – 50 МГц генераторно-резонансным методом с одновременным использованием принципов периодического сравнения и замещения.At the frequency range up to 100 MHz the real dielectric with permittivity e and conductivity λ simulated by twoterminal element of the electric circuit with complex impedance Z~ or complex conductivity L ~ , in which interaction of electromagnetic fields with the investigated substance is provided. The values of real e ¢ and imaginary e¢ parts of the complex dielectric constant e e e ¢ + ¢ = * is calculated based on the geometric factors and measured values of Z~ and L). In a simplest case two-terminal element represents as a parallel or series connected capacitor Cx and resistor Rx. In proposed measuring method the investigated two-terminal element with capacitance Cx and conductance Gx=1/Rx or the reference capacitor С0 and conductance G0 connected periodically to oscillatory LC circuit of electric high frequency generator by automatic switching unit with a frequency Ω<<ω, were ω – eigen frequency of oscillatory LC circuit. The output of the measuring generator is a high frequency package voltage, which is modulated both on frequency and amplitude at a switching frequency Ω. The difference on amplitudes ΔU and frequencies Δω of packet output voltage can be used from direct determination of Cx and Gx, but in this case the total measurement uncertainty include instability of ΔU and Δω measurement channels. In addition, on dielectrics with significant losses, neglect contribution of conductivity difference G0–Gx to the Dw is unacceptable. From this regard, in the laboratory layout for automatic measurement of Cx and Gx the method of inverse substitution principles was applied. The principle of periodic comparison and inverse substitution in generator-resonance method allowed to exclude the impact of the circuit element parameters volatility and thereby improve the accuracy and automate the process of measurement. The developed automated system can measure the capacity of 0,05 pF or more in the frequency range 50 kHz – 50 MHz with accuracy better than 2%. The sensitivity of the circuit to conductance changes and consequently to dielectric losses depends on the frequency and amplitude of the generator voltage, and the type and value of measuring conductivity. In practically studies relative conducted measurement uncertainty Gx does not exceed 5%.
Вплив технічно-естетичних показників якості паковання на попит продукції
(Видавництво Львівської політехніки, 2016) Калініна, Олена; Байцар, Роман; Національний університет “Львівська політехніка”
Розглянуто вплив естетичних показників якості паковання на конкурентоспроможність товарів і їх просування на споживчому ринку, значення низки чинників у формуванні художньо-естетичної складової паковання, а також чинні нормативні документи, які регламентують стандарти на паковання. Рассмотрено влияние эстетических показателей качества упаковки на конкурентоспособность товаров и их продвижение на потребительском рынке, значение ряда факторов для формирования художественно-эстетической составляющей упаковки, а также существующие нормативные документы, регламентирующие стандарты на упаковку. Demand for consumer goods is quite difficult socio-economic category. In the decision to purchase a particular product objectively influenced by factors such as the usefulness of product, price and income of buyer. Appearance of packaging, largely must to help shoppers navigate in the ocean products, introduces him to the principal advantage of goods and helps to make the right choice. Packing regarded as artistic and functional complex that includes three interrelated components: the material and constructive, communicative and informative and artistically shaped. Along with certain characteristics that a quality modern packaging must have , such as environmental friendliness, reliability, lightness, ease of use, portability, possibility of recycling, the expressive aesthetic appearance is prerequisite for competitiveness. When creating attractive, positive for consumer visual "picture" of packaging should take into account certain characteristics of consumer audience. Unconditional and unquestionable influence on visual perception packaging design has national mentality and traditional features, characteristic of the population of a country and certain stereotypes in the perception of the visual image. Yes, always negative impact on demand of commodity will have colors, symbols and signs on the packaging, which historically perceived negatively by citizens of the country, and, conversely, the positive experience of the people, their traditions cause positive emotions, to encourage purchases. For example, in the Middle East blue color associated with mourning, but in Europe it is called royal, red symbolizes the loss in Turkey, while in China it is perceived as a symbol of goodness and joy Age of consumers affects visual perception packaging and hence on the demand of goods too. Thus, the packaging products for children should be attractive for them to have a bright, saturated colors, pleasant to the touch surface. For packaging of goods for teenagers would be appropriate concise, accurate slogans slang phrases, positive characters which common in subculture of teenagers. Brand designers must also take into account the objective gender differences in the perception of packaging for men and women. Also physiological characteristics of men and women directly displayed on differences in purchasing behavior. Color, size, shape of packaging "female" goods traditionally associated with elegance, beauty and charm of women, while the visual image of the "male" goods must emphasize poise, courage, determination of man. So, the shape of the male deodorant "24/7" has restrained rectangular silhouette and a bottle designed for women mimics the configurati of female body. When developing packaging designs undeniable influence on his visual image has a price equivalent of product which this packaging has positioned . Dear goods require of expensive, high-quality, sometimes of exclusive means of its representation. Packaging of luxury goods should speak eloquently about his status. Today designers and marketers to attract buyers are use innovative, increasingly expressive and creative packaging solutions of visual image, using innovative and sometimes extraordinary general idea. Containers used for packaging products must comply with the current standards or specifications and provide storage and immutability of their properties during the warranty period. Type of packaging determined by current regulations. Ukraine's WTO membership and ratification of the Association Agreement between Ukraine and the EU obliges Ukraine to the implementation of international standards governing the modern requirements for packaging consumer products.
Зміст до збірника «Вимірювальна техніка та метрологія» Випуск 77
(Видавництво Львівської політехніки, 2016)
Корекція похибок дрейфу та набутої неоднорідності у термоелектричному перетворювачі з керованим профілем температурного поля
(Видавництво Львівської політехніки, 2016) Кочан, Орест; Національний університет “Львівська політехніка”
Набута термоелектрична неоднорідність термопар та її негативний вплив на похибку вимірювання температури термоелектричними перетворювачами відомі понад століття. Сучасні дослідники вважають її основним джерелом похибки вимірювання температури, а саме явище однозначно негативним. Однак останнім часом запропоновано ефективні методи боротьби з цією похибкою. Розроблено підхід, що дає змогу використати набуту термоелектричну неоднорідність термопар для оцінювання метрологічних характеристик термоелектричних перетворювачів. Приобретенная термоэлектрическая неоднородность термопар и ее негативное влияние на погрешность измерения температуры термоэлектрическими преобразователями известны больше столетия. Современные исследователи считают ее главным источником погрешности измерения температуры, а само явление однозначно негативным. Однако в последнее время предложены эффективные методы борьбы с этой погрешностью. В статье предложен подход, позволяющий использовать приобретённую термоэлектрическую неоднородность термопар для оценки метрологических характеристик термоэлектрических преобразователей. Thermocouples are the most popular sensors of temperature used in measuring praxis for temperatures in the range 600–2500 ºC, in spite of their drawbacks. The most important among them is their error, which is often too big for many cases in industry and science. The total error of thermocouples is much greater than that of their measurement channels. The main errors proper for thermocouples are as follows: 1. Considerable initial deviation of their conversion characteristic (CC) from the nominal one. The likely deviation in CC for the most popular type of thermocouples (type K) may reach 5,5 °C at 600 °C and 8 °C at 1100 °C. 2. Considerable drift of CC during operation at high temperatures, that is a change of CC in time. It may vary in the range of 0,5 °C to 10 °C for the mentioned above type K of thermocouples during 1000 hours at 600 °C or at 1100 °C respectively. 3. Thermoelectric inhomogeneity of thermocouple legs acquired during operation at high temperatures. The error due to inhomogeneity may reach 10 °C when measuring 1100 °C during 1000 hours using type K thermocouples, or even more in some cases. The error due to acquired inhomogeneity stems from changes in thermocouple legs at high temperatures in time. These changes are caused by the effect of chemical and physical processes (such as oxidation, diffusion, recrystallization etc.) in legs. If a thermocouple is split into imaginative sections, each section operates at its own temperature. That is the reason why, during prolonged operation, CC of each section changes in time in accordance with its particular operating temperature. If the temperature field along the thermocouple legs changes, the temperatures of each section changes correspondingly. Therefore, the error of each section is not constant, so the total error of a thermocouple varies even when the temperatures of the measuring and the reference junctions remain constant. This is an appearance of the error due to thermoelectric inhomogeneity when the developed emf depends on the distribution of temperature along thermocouple legs. Many researchers consider that it is the main reason of thermocouple error. Sometimes the high thermocouple error after extended use is thought to be inevitable and impossible to correct. However, recent studies have discovered new methods for decreasing the influence of the error due to acquired inhomogeneity on measurements of temperature using thermocouples. There are three stages of understanding of the error due to inhomogeneity during the history of thermocouples. The first stage began in 1906, when the problem of the inhomogeneity in thermocouples was posted. Since then the problem has been studied by various researchers. In 1976 professor Kirenkov drawn conclusion that inhomogeneous thermocouples cannot be used in measuring praxis because of a big error which is impossible either to correct orcompensate. No methods how to deal with the error due to acquired during operation inhomogeneity were suggested.This is the second stage of the problem – direct prohibition of use of inhomogeneous thermocouples. The third stage began in 1984, when some methods of correction for the error due to inhomogeneity were suggested. The first of them was thermocouple calibration in situ, or in a temperature field similar to that of operation. Also the method for computation of the thermocouple error in an operating conditions based on the thermocouple calibration in a laboratory was suggested in the same year. However, the most effective method for compensating the error due to inhomogeneity was suggested in 2006. The idea of the method is to stabilize a temperature field along a thermocouple using additional subsystems for temperature control. Implementation of the method requires a new sensor which was suggested in 2006 and was called the thermocouple with controlled profile of temperature field. This is the third stage of the problem. At this stage some effective methods to compensate the error due to inhomogeneity were suggested. This paper suggest the next stage, that is the fourth one, which implies development of the method suggested in 2006 and the thermocouple with controlled profile of temperature field. The idea of the stage is to use thermoelectric inhomogeneity of thermocouples to assess the metrological properties of thermoelectric thermometers.
Експериментальні дослідження залежності вимірюваної температури від частоти антистоксової компоненти спектра комбінаційного розсіювання світла для AL2O3
(Видавництво Львівської політехніки, 2016) Кривенчук, Юрій; Микитин, Ігор; Сегеда, Олег; Національний університет “Львівська політехніка”
Al2O3 – наноструктурований дрібнодисперсний порошок, який часто використовується як сорбент для очищення води, в матеріалознавстві, для виготовлення конденсаторів. Подано результати експериментальних досліджень спектрів комбінаційного розсіювання світла для Al2O3 у температурному діапазоні від 18 до 70 °С. Знайдено еквівалентну частоту антистоксової компоненти спектра комбінаційного розсіювання світла методом центра мас, також отримано аналітичні залежності еквівалентної частоти антистоксової компоненти спектра комбінаційного розсіювання світла від температури. Досліджено залежність похибки апроксимації від кількості коефіцієнтів апроксимаційної кривої. Обладнання для експериментів: лазер ν = 632,9 нм, спектроаналізатор MS 3501i, оптична схема з використанням вузькосмугового фільтра та призми. Дослідження проводили за нормальних умов. Представлены результаты экспериментальных исследований спектров комбинационного рассеяния света для Al2O3 в температурном диапазоне от 18 до 70 °С. Найдено эквивалентную частоту антистоксовой компоненты спектра комбинационного рассеяния света методом центра масс, также получены аналитические зависимости эквивалентной частоты антистоксовой компоненты спектра комбинационного рассеяния света от температуры. Исследованы зависимость погрешности аппроксимации от количества коэффициентов аппроксимационной кривой. Оборудование для экспериментов: лазер ν = 632,9 нм, спектроанализатор MS 3501i, оптическая схема с использованием узкополосного фильтра и призмы. Исследования проводились при нормальных условиях. On the basis of Raman known at present are two ways to measure temperature. The first and most more common method of measuring temperature by Raman intensity is dependent stokes and antistokes Raman component. This method is relatively simple to implement, since change with temperature integrated area antistokes and stokes component. This method of temperature measurement by Raman has good sensitivity and accuracy, but has several significant drawbacks. The main drawback is a methodological error that occurs as a result of determining the area of integrated antistokes and Stokes components. Spectrophotometer to measure consistently first Stokes then antistokes component of Raman spectroscopy, the measurement time of stokes components of the object and is heated by laser heating antistokes components that it leads to error. Another way is to measure the frequency shift Raman. To measure the temperature shift frequency Raman enough to determine just antistokes component Raman spectroscopy. To measure the temperature shift frequency Raman frequency is not appropriate to use a spectrophotometer and spectrum analyser. The peculiarity of the spectrum analyser is that it measures only antistokes component, and the full range of a whole, not just a stepping stone that can reduce the methodological error. Also unconditional significant advantage of this method within the temperature measurement by Raman is speed. By comparison when measuring the temperature integrated area ratio of the maximum speed is 13 seconds, and the Raman shift frequency of 1 second. By reducing the measurement time is reduced further methodological error caused by heating of the object studied laser. Therefore, based on this method conducted research described in the article. The results of experimental studies Raman spectroscopy for Al2O3 in the temperature range of 18 to 70 °C. Each point temperature for 10 implementations derived components range antistokes Raman method of centre of mass calculated value equivalent frequency components antistokes Raman spectroscopy, and the average value of the equivalent frequency components antistokes range and uncertainty determine an equivalent frequency components antistokes. Analytical dependences equivalent frequency components antistokes Raman spectrum of temperature. The dependence of error of approximation of the number of coefficients approximating curve for each of the objects, and certainly the best number of factors. Equipment using experiments were conducted: laser ν = 632,9 nm spectrum analyser MS 3501i, optical circuit using a narrow band filter and prism, studies were conducted under normal conditions.
Математичнемоделювання якості підземних трубопроводів в умовах корозійної втоми
(Видавництво Львівської політехніки, 2016) Юзевич, Лариса; Національний університет “Львівська політехніка”
Розроблено рекомендації щодо оцінювання довговічності та якості підземних металевих трубопроводів в умовах втоми. Встановлено особливості раннього виявлення кризових (передаварійних) ситуацій. Розроблено методику розрахунку ризику в смузі проходження траси трубопроводу з урахуванням його технологічної специфіки і впливу місцевих чинників різної природи на можливість розвитку аварії. Разработаны рекомендации относительно повышения качества математических моделей мониторинга сложных объектов техники с низким уровнем динамики процессов, которые характеризуются особенностями раннего выявления кризисных (предаварийных) ситуаций. The presence of fatigue cracks on the surface of metallic underground pipelines sharpens the problem of calculation values of strength characteristics at the action of corrosive environments, that did not find the complete decision nowadays. In this connection it is needed to correct the row of defects and normative and technical documents related to insufficient actuality of corresponding. In normative documents from exploitation of construction elements on this time the reasonable norms of legitimate values of corrosive damages, reduction of bearing strength of construction elements are absent. It creates complications in the ground of normative terms of exploitation and evaluation of the maximum state of metallic constructions, in planning of charges on exploitation of construction elements and repair and restoration work. An object of researches is underground metallic pipelines that are in the conditions of corrosion-fatigue destruction. The subject of a study is normative document. It is expedient to specify and perfect on the basis of the information got on results monitoring of functioning of underground metallic pipelines. Aim of this article – formulation of criteria and scientifically reasonable recommendations for providing of quality of underground metallic pipelines exploitation in the conditions of fatigue and influence of aggressive environment, and also forming of normative principles in sphere of pipeline transport. Only underground main gas pipelines in the ground electrolyte in the conditions of low cycle fatigue should be considered. For the improvement of normative documents it is expedient to build a complex mathematical model, that will unite the physical and chemical model of corrosion-fatigue processes, model of piling up description of damages in metals and elements theory of risks. For the modeling of speed increasing of fatigue crack on the middle rectilineal area of kinetic curve equation that binds length of fatigue corrosive crack and amount of cycles of loading to the coefficient of intensity of mechanical tensions is used. Corresponding equation is improved for a metal in corrosive environment and the pH-value of environment, and also electrode potential of metal, is here taken into account. For the base model of damage accumulation for metals in the conditions of irregular deformation a model that is based on the curvilinear change of damages, and power going is used near description of process of low cycle fatigue, that is a base on criterion of fatigue strength of V. T. Troschenko. Critical specific work that answers the origin of fatigue crack is included in a criterion. For description of the irregular cyclic loading of metal expression, power descriptions of metal and function of relative value of amplitude intensity of tensions, that characterizes the degree of mechanism influence of fatigue on the fatigue curve is also used. Evolutional equation is written in for the modeling of low cycle fatigue of metals. Lviv Polytechnic National University Institutional Repository http://ena.lp.edu.ua Вимірювальна техніка та метрологія, №77, 2016 р. 137 Correlation for description of low cycle corrosion fatigue of material in metallic underground pipelines is complemented by equations for the evaluation of risks within the limits of investment project that executes corresponding organization (enterprise). For optimization of informative streams of enterprise and improvement of the defence system of metallic underground pipelines from a corrosive fatigue the quality functional is used taking a feed-back in methodology of risk evaluation of investment project into account. The aim of that application is the improvement of the corresponding normative and technical providing. In zones with non-stationary plasticity strain it is expedient to use the criteria of adhesion strength, biocorrosive aggressiveness of soils, mechanical criterion for the coefficient of intensity of tensions (the overstrain of corrosive process takes into account), the criterion of corrosive stability of pitting, criterion correlation for the evaluation of speed of stability corrosion of metal in the defect of isolating coverage together with entered by diagnostic weight of signs and diagnostic value of inspections, that will complement, will specify and will perfect the system of the corrosive monitoring of pipelines and able to be used for control of corrosive process. With their help optimization of terms of construction elements defence of oil and gas industry, that is described and regulated by a state standard, can be conducted. As a result a new complex mathematical model is offered in relation to upgrading of corrosion protection of metallic underground pipelines from positions of corrosion fatigue, electrochemistry, physics of surface processes, mechanics of destruction and theory of risks. The conducted modeling takes piling up of damages in metals into account and allows to study the mechanisms of distribution of corrosive fatigue cracks in underground metallic pipelines that are in aggressive environments, in particular, in saltwater and ground electrolyte. The results of mathematical modeling are the basis of methodology development and improvement of normative and technical documents for metallic underground pipelines, that are under the action of the regular and irregular cyclic loading in the conditions of low cycle corrosive fatigue. The joint use of corrosive fatigue criteria and corrosive monitoring criteria of pipelines offered in this article will allow in detail enough from positions of corrosive fatigue, electrochemistry, physics of surface processes, mechanics of destruction and theory of risks to study the mechanisms of distribution of corrosive fatigue cracks in underground metallic pipelines that are in aggressive environments.
Накладний індуктивний перетворювач для магнітної дефектометрії
(Видавництво Львівської політехніки, 2016) Дейнека, Ростислав; Національний університет “Львівська політехніка”
Сутність електромагнітних методів неруйнівного контролю феромагнетиків полягає у виявленні магнітного поля, що виступає над внутрішніми і підповерхневими дефектами. Для виявлення такого локального поля запропоновано новий варіант накладного давача у вигляді індуктивного елемента на тороїдальному осерді з додатковими магнітопроводами. Цей давач має просту конструкцію, його висока чутливість підтверджена експериментально. Такий давач може використовуватись для контролю зварних з’єднань запропонованим методом, що ґрунтується на вимірюванні магнітного опору ділянки зварювання. Сущность электромагнитных методов неразрушающего контроля ферромагнетиков состоит в выявлении магнитного поля, выступающего над внутренними и подповерхностными дефектами. Для выявления локального магнитного поля предложен новый вариант накладного датчика в виде индуктивного элемента на тороидальном сердечнике с дополнительными магнитопроводами. Этот датчик имеет простую конструкцию и высокую чувствительность, подтвержденную экспериментально. Такой датчик может использоваться для контроля сварных соединений предложенным методом, основанным на измерении магнитного сопротивления участка сварки. The essence of electromagnetic methods of nondestructive ferromagnets testing consists in identifying the lines of ledge of the external magnetization constant magnetic field that is scattered on interior and subsurface defects. Existing electromagnetic methods differ only by ways of local magnetic inhomogeneity detections. For detecting the local magnetic field the new variant of the plated sensor for nondestructive testing of ferromagnetic materials in the form of an inductive element on a toroidal core with magnetoconductive elements was proposed. The sinusoidal audio frequency voltage from the generator with amplitude at which the core material begins to enter into the saturation stage is supplied in winding. The magnetic field of an internal defect straying through internal lining magneto conductive linings sub magnetizes the ferrite core, and is summed up with the field from the generator, that is leading to saturation of the core coil, losses the inductance and increase current in the coil. To measure the saturation current series with the winding turns on the low resistor, which voltage is measured, and it determines the size of the defect. Inductive sensor has a simple design and high sensitivity (output voltage increase more than 5 times), confirming by the experimental investigation of its model. The proposed sensor is insensitive to the presence of extraneous ferromagnetic objects, and only responds to a magnetic field and can be used for monitoring welds of steel elements by measuring the magnetic resistance of some consecutive areas of the consistent weld in the transverse direction. The magnetic resistance value of the weld at most depends on the presence of cracks, cavities, pores and other non-magnetic inclusions having negatively affect on the strength of the connection. The magneto motive force determination in the control area is carried by means of the inductive magnetic field sensor. The internal high magnetic resistance of the sensor is much larger than its poles contact resistance and resistance of the defect area, and therefore does not affect on its stray field. It does not matter how the intensity of the ledge field in the section of the seam changes because the welding defect has increased magnetic resistance and the quality of welding is defined by the range of this resistance The magnetic flux of the applied field to determine the magnetic resistance control areas is measured by means of an optional magnetic flux sensor installed in one of the pole pieces of the magnetized device. Since the pole piece has a constant value of the magnetic resistance, the output voltage of the additional sensor further will depend on the magnitude of the magnetic flux of the magnetized device. This means that irregularities of detail surfaces will be taken into account in determining the magnetic resistance of the defect area.
Вдосконалення цифрових термометричних засобів для досліджень сонячних колекторів
(Видавництво Львівської політехніки, 2016) Василиха, Христина; Яцук, Василь; Здеб, Володимир; Яцук, Юрій; Національний університет “Львівська політехніка”
Проаналізовано вимоги до метрологічних параметрів цифрових вимірювачів температури та різниці температур для досліджень сонячних колекторів. Подано результати експериментальних досліджень взаємозамінності напівпровідникових перетворювачів температури з метою створення температурних сенсорів. Встановлено, що у цифрових термометричних засобах найдоцільніше використовувати послідовно сполучені транзисторні діоди, у яких можна зменшити значення розкиду спадків напруги та близькі до гранично можливого значення коефіцієнта ідеальності. Розроблено структури цифрових вимірювачів температури та різниці температур і вдосконалено методики коригування їх адитивних і мультиплікативних складових похибки. Проведен анализ требований к метрологическим параметрам цифровых измерителей температуры и разности температур для исследований солнечных коллекторов. Представлены результаты экспериментальных исследований взаимозаменяемости полупроводниковых преобразователей температуры с целью создания температурных сенсоров. Установлено, что в цифровых термометрических средствах целесообразно использовать последовательно соединенные транзисторные диоды, при этом можно уменьшить значения разброса падений напряжения и близкие к предельно возможному значения коэффициента идеальности. Разработаны структуры цифровых измерителей температуры и разности температур и усовершенствованы методики корректировки их аддитивных и мультипликативных составляющих погрешности. The analysis of requirements for metrological parameters of digital temperature meters and temperature difference meters for solar collectors’ investigations been done in the article. Under the regulations requirements a minimum temperature drop not exceed 1,5 K, and for the maximum relative error of temperature measurement not more ±2% it provide the absolute error of temperature drop measurement near ±0,030 K, and their measurement unit list significant digit 0,01 K. This error value of temperature drop measurement can be achieved if it makes a temperature sensor calibration in the precision thermostat or rigorous recruiting of sensors pairs. The experimental research of the transistor diodes interchangeability to create precise, stable and low cost temperature sensors is carried out also. It showed that transistor diodes should be given preference, which fabricated in the same technological cycle especially as SMD transistors. The theoretical assumption about the initial voltage spread reduction of the SMD transistors compared with traditional volumetric installation transistors is experimentally confirmed. The spread values were reduction from ±5 K for volumetric installation to ±0,3 K for SMD transistors. For further spread reduction of the forward bias diode voltage it proposed connect transistors in series, which additionally allowed increase their sensitivity. The temperature sensor prototype as series-connected transistors are mounted on printed circuit boards and sealed (placed in thermocontractable tube with the screened leads) to prevent water ingress. The entire experimental setup was placed in a passive water-zero thermostat to ensure the minimum values of the temperature gradients among the several sensors. Among the several mass-produced investigated type transistors, it was selected two transistors type BCW61C and BC849C, which should be the lowest values of the voltage drop spread ±457 μV (±0,22 К) and ±406 μV (±0,20 К) accordingly. While design this enables the provision of measuring temperature drop standard deviation of five series connected diodes not exceed ± 0,46/ 10 = ±0,16 К with a simultaneous increase the temperature and temperature drop measurement sensitivity to 10 mV/K. While the digital thermometers design it very important are the ideality factor and the base resistance of the diodes-transistors, which their means are determined from the proposed equations. On the experimental data basis the transistors type BCW61C and ВС849С ideality factors was calculated η=1,18380 and η=1,00048 respectively, and their base resistance amounted near 50 Ohm which corresponds to practical recommendations for the selection transistors as temperature sensors.The structures of digital temperature and difference temperature meters were developed too. The methods of adjusting their additive and multiplicative error components are improved. The digital temperature meter structure contains the current-defining generator, current resistor, several standard resistors, voltage reference, ADC and device controller. The digital thermometer transform function was set, which allowed establish the metrological requirements for its constituent elements. It shown that designed scheme should be used amendments method in order to set the precision thermometer requirements while the relaxed instrumental error their components requirements. The digital meter of temperature difference can be built on the basis of series-connected diode sensors that provide high accuracy, sensitivity, resolution and performance, especially when used in the radiometer with electrical substitution. Two possible methods of digital thermometer introducing amendments in the analog and digital forms is described. It also showed their strengths and weaknesses and advised to use tuning in digital form. Structure of designed digital temperature difference meters is based on the ADC implementation with differential inputs, which it both signal exits was connected to the both current generators outputs. The ADC reference voltage formed by the precise resistive voltage divider. In the manufacturing process it can be adjusted as mentioned additive and multiplicative error components by using two temperature points. Adjustments additive error component generally convenient to carry an arbitrary temperature, for example, equal to ambient temperature. And to adjust the multiplicative error component it advisable to use a standard thermometer and further the conversion factor changing by any of the conversion path scale elements. If ten semiconductor temperature sensors implement it significantly reduced requirements for sensitivity threshold of second devise transformative elements because LSB units 0,001 K complies the input voltage 10 μV, that is much higher than the sensitivity threshold of modern scale elements. Except proved the feasibility of the proposed temperature sensors in designed digital meter temperature and the temperature difference, they should be applied in other areas such as food processing industry and individual heating counters, namely accounting of consumed heat by individual consumers.
Метод вимірювання електричних параметрів великогабаритних антенних систем
(Видавництво Львівської політехніки, 2016) Паламар, Михайло; Поіхало, Анатолій; Стрембіцький, Михайло; Кругльов, Володимир; Тернопільський національний технічний університет ім. І. Пулюя; Національний центр управління і випробування космічних засобів
Запропоновано метод і розроблено методику вимірювання та оцінювання електричних параметрів великогабаритних антенних систем для надвисоких частотних діапазонів, що не були передбачені для використання на таких антенах під час їх проектування. На основі запропонованої методики проведено експериментальні дослідження і наведено результати вимірювання та метрологічної оцінки радіотехнічних параметрів двох великогабаритних антенних систем з діаметрами рефлекторів 12 м для частотних діапазонів Ка і Кu. Проаналізовано можливість використання таких антенних систем для створення сучасних систем космічного зв’язку. Предложен метод и разработана методика измерения и оценки электрических параметров крупногабаритных антенных систем для сверхвысоких частотных диапазонов, которые не были предусмотрены для использования в таких антеннах при их проектировании. На основе предложенной методики проведены экспериментальные исследования и приведены результаты измерения и метрологической оценки радиотехнических параметров двух крупногабаритных антенных систем с диаметрами рефлекторов 12 м для частотных диапазонов Ка и Кu. Проанализирована возможность использования таких антенных систем для создания современных систем космической связи. Ключевые слова: антенная система, диаграмма направленности, космическая связь, система управления, погрешность наведения, эффективная площадь раскрыва поверхности антенны. The method of measurement and evaluation of electrical parameters a larg antenna systems for ultra-high frequency bands is developed, that were not provided for the use of such antennas by their design. For ensure the necessary radio parameters in professional antenna systems (AS) use parabolic antenna reflectors with large diameters of 5 to 12 meters or more. The creation of such antennas require large expenditures for their production and metrological support by parameters setting. In addition many antenna systems of military-industrial complex (MIC) which used in the frequency bands up to 4 GHz require modernization during the transition to higher frequencies and metrological evaluation their electrical parameters at the facility. The measurement of parameters of radio reflector AS large-diameter is impossible to implement by ground methods at a sufficiently high angles to avoid the influence of topography on Earth passing radio-waves. The measurement by radio astronomy method with using aircrafts with known parameters of source signal requires large expenditures and complex preparatory work. Therefore we need other complex methods. The essence of the proposed method is to conduct multi-parameter measurement electrical parameters AC by radio astronomy method with using an unknown source signals from satellites and use the auxiliary test antenna relatively small diameter (Ø 2,4 m). First measured the electrical parameters of the auxiliary antenna, namely the width direction of the diagram, the gain coefficient, coefficient of using the surface. Then measured the same parameters of auxiliary test antenna by radio astronomy method with using an unknown source signals from satellites and finding corrective coefficients. The next step is the measurement by radio astronomy method the antenna which studied with large diameter of reflector with using the source signal from the same satellites and then recalculate parameters with using corrective coefficients. Based on the proposed method is provided the experimental studies and the results of measurement and metrological evaluation of radio parameters of two large antenna systems with diameters of reflectors 12 meters for frequency bands Ku (11,7–12,5 GHz) and Ka (17,3–18,1 GHz ). The possibility of using such antenna systems for create a modern space communications systems is analyzed, especially for establishment of ground control station Ukrainian satellite “Lybid”. Creation of satellite stations through the use of effective technological measures, including AS TNA-57 by their upgrading would considerably reduce the cost of establishing such stations.