Academic literature on the topic 'Flaw detector'

Master of Science<br>Food Science Institute - Animal Sciences & Industry<br>Jayendra K. Amamcharla<br>High-protein dairy powders are added to a variety of products to improve nutritional, functional, and sensory properties. To have the intended properties, the powder must be soluble. The solubility is effected by processing storage, and dissolution conditions, as well as the type of powder. Various tests are used to determine solubility, but they are time-consuming and subjective. Literature has shown that ultrasound spectroscopy can characterize the solubility of high-protein dairy powders, but it requires expensive equipment and skilled technicians. An economical alternative is to use an ultrasonic flaw detector, which is commonly used in the construction industry. For this study, an ultrasonic flaw detector based method was developed to characterize the solubility of high protein dairy powders. To evaluate the method, commercially available milk protein concentrate (MPC) was obtained and stored at 25°C and 40°C and stored for four weeks to produce powders with different dissolution properties. To test the powders, a 5% (w/w) concentration of powder was added to water. A focused beam reflectance measurement (FBRM) and solubility index were used as a reference method. After powder addition, data was collected at regular intervals for 1800s. The FBRM and solubility index showed that the powders lost solubility as the storage time and temperature increased. From the ultrasound data, one parameter was extracted from the relative velocity and three parameters were extracted from the attenuation data. A soluble powder had a low relative velocity standard deviation from 900-1800s, high area under the attenuation curve, low peak time, and high peak height. The ultrasonic flaw detector detected differences in solubility before the solubility index. When testing MPC with protein contents ranging from 85% to 90% and at a dissolution temperature of 40°C and 48°C, data from the ultrasonic flaw detector and FBRM showed that the solubility decreased as the protein content increased and increasing the dissolution temperature improved the solubility of the powder. Overall, the ultrasonic flaw detector can characterize the solubility of high-protein dairy powders.

Диссертация на соискание научной степени кандидата технических наук по специальности 05.11.13 - приборы и методы контроля и определения состава веществ. – Харьковский национальный университет радиоэлектроники, Харьков, 2015 г. Диссертация посвящена разработке метода и прибора для эффективного контроля дефектов структуры тонких неферромагнитных пленок. Рассмотрены общие положения применения вихретоковых преобразователей в дефектоскопии. Показаны характерные общие принципы построения вихретоковых дефектоскопов. Указаны направления улучшения метрологических показателей вихретоковых дефектоскопов тонких пленок. Выполнен анализ дефектов структуры тонких неферромагнитных пленок и методов контроля качества. Проведен анализ характеристик апериодических ВТП, способных выявлять указанные дефекты. Уточнена теория апериодических ВТП с учетом анализа влияния на характеристики преобразования внутреннего сопротивления источников питания и параметров нагрузки. Выполнен анализ характеристик вихретоковых резонансных ВТП предназначенных для выявления дефектов тонких неферромагнитных пленок. Рассмотрены различные режимы работы ВТП с учетом внутреннего сопротивления источника питания и сопротивления нагрузки, способы подключения ВТП к источнику и т.д. Выполнен анализ характеристик, даны сравнительная оценка и рекомендации, обосновавшие схемные решения и параметры ВТП. Доказаны преимущества резонансных ВТП относительно апериодических. Проведен анализ факторов, влияющих на точность выявления дефектов тонких неферромагнитных пленок средствами высокочастотной резонансной вихретоковой дефектоскопии. Показано, что одним из основных факторов, влияющих на точность измерений в резонансной вихретоковой дефектоскопии, является нестабильность рабочего зазора ВТП. Предложен вариант компенсации влияния изменения рабочего зазора при использовании резонансного ВТП накладного типа, работающего на двух различных частотах. Разработан способ резонансной дефектоскопии, позволяющий улучшить выявление дефектов в тонких неферромагнитных пленках. Исследована модель оценки взаимодействия резонансного ВТП с неферромагнитной тонкой пленкой. Приведены аналитические соотношения, проведены расчеты зависимости выходного сигнала от параметров ВТП. Для практического подтверждения аналитических положений работы выполнены экспериментальные исследования: влияние отдельных параметров резонансного ВТП на его основную характеристику преобразования; выбор рабочей частоты; поиск наиболее целесообразного способа создания компенсационного напряжения; уточнение особенностей работы трансформаторных ВТП на цилиндрических и плоских катушках; выбор типа ВТП и схемы его включения. Создан дефектоскоп, позволяющий выявлять дефекты структуры тонких неферромагнитных пленок.<br>Dissertation for the degree of Ph. D. in Engineering Science, specialty 05.11.13 – devices and methods of control and determination of the composition of substances. – Kharkov National University of Radio Electronics, Kharkov, 2015. The dissertation is devoted to the development of methods and instruments for the effective control of defects imperfections film structure The analysis of the characteristics of various ECP capable of detecting these defects. Considering the various modes of operation, taking into account the internal resistance of the power supply and the load resistance, how to connect to a power source ECP. Developed a way to improve the detection of defects in non–ferromagnetic thin films. A model to assess the interaction with non–ferromagnetic resonance ECP thin film. These analytical ratios were calculated according to the output signal from the parameters of the ECP. For experimental research laboratory prototype was manufactured eddy–current flaw detector by which to check whether the calculation of the theoretical and experimental relations.

Диссертация на соискание ученой степени кандидата технических наук по специальности 05.11.13 – Приборы и методы контроля и определение состава веществ. – Национальный технический университет "Харьковский политехнический институт", Харьков, 2015. В диссертационной работе решается проблема повышения помехоустойчивости феррозондовых дефектоскопов к магнитным полям помех, вызванных конечными размерами контролируемых деталей, их ступенчатыми и галтельными переходами, магнитной неоднородностью ферромагнитного материала. Анализ существующих методов подавления помехи, вызванной сторонним магнитным полем, показал, что основным способом устранения помехи в настоящее время является включение обмоток феррозондов по градиентометрической схеме. Однако этот метод не свободен от недостатков, так его эффективность низка при высоком уровне градиента поля помехи и коэффициент преобразования феррозонда в большей степени зависит от геометрических параметров магнитной системы и расположения полуэлементов феррозонда относительно дефекта. Не свободен от недостатков метод экранирования феррозонда, так как экран значительно увеличивает размеры преобразователя, что затрудняет его использование на ступенчатой поверхности детали. Обзор методов и способов подавления помехи показал, что наиболее эффективным является метод, основанный на использовании двух феррозондов, один из которых является измерительным, а второй – компенсационным. При этом необходимо, чтобы измерительный феррозонд имел достаточную чувствительность, как к магнитному полю дефекта, так и к полю помехи, а компенсационный феррозонд имел высокую чувствительность только к полю помехи и практически не реагировал на поле дефекта. Для теоретического обоснования эффективности предлагаемого метода была разработана математическая модель поля вектора намагниченности, как в области всей детали, так и в локальной области расположения дефекта. Напряженность магнитного поля в сердечниках феррозонда, индуцированного намагниченностью детали и дефекта, рассчитывается путем применения модифицированной теоремы о взаимности К. М. Поливанова. Сердечники измерительного и компенсационного феррозонда являлись полузамкнутыми U-образной формы. Компенсационный феррозонд имеет перемычку непосредственно над дефектом и шунтирует его магнитное поле. Предложен метод расчета магнитного поля помехи индуцированного намагниченной деталью, основанный на решении интегрального уравнения с использованием линейной аппроксимации функции намагничивания, что сокращает порядок системы алгебраических уравнений. Предложен метод расчета коэффициента передачи мостовой электрической схемы феррозонда, при которой уменьшается вдвое число обмоток и создается возможность получения увеличенного его коэффициента передачи за счет явления параметрического резонанса, упрощается балансировка обмоток феррозонда.<br>Thesis for granting the Degree of Candidate of Technical sciences in speciality 05.11.13 – Devices and methods of testing and materials structure determination. – National technical university "Kharkiv Politechnical Institute", Kharkiv, 2015. In the thesis the problem of improving the noise immunity of fluxgate flaw detector to interference’s magnetic fields caused by the finite size of controlled items, their step and fillet connections, the magnetic inhomogeneity of ferromagnetic material has been solved. The method of calculating the magnetic field interference induced by the magnetized part, based on the solution of the integral equation using a linear approximation of the function of the magnetization, which reduces the order of the system of algebraic equations has been proposed. As a transmitter error-correcting ferroprobe flaw is proposed to use a block of the magnetic system consisting of two identical ferroprobes with a U-shaped core. The results of numerical and field experiments have shown that the magnetic flux in the core flux gate with a U-shaped core, with a jumper directly above a defect is 8-12 times smaller than the flow of measurement (main) ferroprobe.

Дисертація на здобуття наукового ступеня кандидата технічних наук за спеціальністю 05.11.13 – Прилади і методи контролю та визначення складу речовин. – Національний технічний університет "Харківський політехнічний інститут" Харків, 2015. У дисертаційній роботі вирішується проблема підвищення перешкодостійкості ферозондових дефектоскопів до магнітних полів перешкод, викликаних кінцевими розмірами контрольованих деталей, їх ступінчастими ї галтельними переходами, магнітною неоднорідністю феромагнітного матеріалу. Запропоновано метод розрахунку магнітного поля перешкоди, індукованого намагніченою деталлю, заснований на вирішенні інтегрального рівняння з використанням лінійної апроксимації функції намагнічування, що скорочує порядок системи алгебраїчних рівнянь. У якості вимірювального перетворювача перешкодостійкого ферозондового дефектоскопа пропонується використовувати блок магнітної системи, що складається з двох ідентичних ферозондів з U-подібними осердям. Результати численних і натурних експериментів показали, що магнітний потік в осерді ферозонду з U-подібним осердям, з перемичкою, розташованою безпосередньо над дефектом, в 8-12 разів менше потоку вимірювального (основного) ферозонду.<br>Thesis for granting the Degree of Candidate of Technical sciences in speciality 05.11.13 – Devices and methods of testing and materials structure determination. – National technical university "Kharkiv Politechnical Institute", Kharkiv, 2015. In the thesis the problem of improving the noise immunity of fluxgate flaw detector to interference’s magnetic fields caused by the finite size of controlled items, their step and fillet connections, the magnetic inhomogeneity of ferromagnetic material has been solved. The method of calculating the magnetic field interference induced by the magnetized part, based on the solution of the integral equation using a linear approximation of the function of the magnetization, which reduces the order of the system of algebraic equations has been proposed. As a transmitter error-correcting ferroprobe flaw is proposed to use a block of the magnetic system consisting of two identical ferroprobes with a U-shaped core. The results of numerical and field experiments have shown that the magnetic flux in the core flux gate with a U-shaped core, with a jumper directly above a defect is 8-12 times smaller than the flow of measurement (main) ferroprobe.

Дисертація на здобуття наукового ступеня кандидата технічних наук за спеціальністю 05.11.13 - прилади і методи контролю та визначення складу речовин. – Харківський національний університет радіоелектроніки, Харків, 2015 р. Дисертація присвячена розробці методу і приладу для ефективного контролю дефектів структури тонких неферомагнітних плівок. Проведено аналіз характеристик різних ВСП, здатних виявляти зазначені дефекти. Розглянуті різні режими роботи з урахуванням внутрішнього опору джерела живлення і опору навантаження, способи підключення ВСП до джерела живлення. Розроблено спосіб, що дозволяє поліпшити виявлення дефектів у тонких неферомагнітних плівках. Досліджено модель оцінки взаємодії резонансного ВСП з неферомагнітною тонкою плівкою. Наведено аналітичні співвідношення, проведено розрахунки залежності вихідного сигналу від параметрів ВСП. Для експериментальних досліджень був виготовлений лабораторний макет вихрострумового дефектоскопа, за допомогою якого здійснювалася перевірка відповідності розрахункових теоретичних співвідношень з експериментальними.<br>Dissertation for the degree of Ph. D. in Engineering Science, specialty 05.11.13 – devices and methods of control and determination of the composition of substances. – Kharkov National University of Radio Electronics, Kharkov, 2015. The dissertation is devoted to the development of methods and instruments for the effective control of defects imperfections film structure The analysis of the characteristics of various ECP capable of detecting these defects. Considering the various modes of operation, taking into account the internal resistance of the power supply and the load resistance, how to connect to a power source ECP. Developed a way to improve the detection of defects in non–ferromagnetic thin films. A model to assess the interaction with non–ferromagnetic resonance ECP thin film. These analytical ratios were calculated according to the output signal from the parameters of the ECP. For experimental research laboratory prototype was manufactured eddy–current flaw detector by which to check whether the calculation of the theoretical and experimental relations.

The main objective of this work is to design the BEta-deLayEd Neutron detector (BELEN) detector for FAIR (Facility for Antiproton Ion Research). The purpose of this detector is the measurement of neutron emission probabilities after ß-decay. The detector consist on a set of 3He tubes embedded in a polyethylene matrix. The design of the detector has been developed using Monte Carlo simulations with MCNPX and GEANT4 codes. The aim of these simulations was to choose a positon of tubes to achieve the maximum neutron detection efficiency while keeping a flat efficiency along the expected energy range for the neutrons. Prior to FAIR detector design, we have developed BELEN-20B prototype with 20 tubes and a mean efficiency for the energy range up to 2 MeV of 43% and BELEN-30 prototype with 30 tubes and a mean efficiency for the energy range up to 2 MeV of 38%. For the characterization of the BELEN-30 it was used a 252Cf neutron source at GSI laboratory, where the BELEN detector join in an experiment using the FRS (Fragment Separator) facility. The data obtained was in concordance with the result of the simulation. Also it has been designed the DESPEC candidates, with 48 tubes, BELEN-48 (AIDA), BELEN-48M1 and BELEN-48M2 with mean efficiency for the energy range up to 5 MeV of 38%, 41%, 55% respectively. The BELEN-48M1 efficiency was measured at PTB with a 252Cf neutron source and with some nuclear reactions that took place on targets located at the center of the BELEN symmetry axis. The results obtained with the 252Cf neutron source was according to the simulations. For some nuclear reactions there were some discrepancies with the expected values. Finally, we proposed a configuration for the future experimental campaigns to measure ß-delayed multiple neutron emission properties at the RIKEN Nishina Center. This detector called BRIKEN (Beta-delayed neutron measurements at RIKEN) will consist of 174 3He tubes (from UPC+GSI+ORNL+RIKEN). The design of all these detectors, has served to define a methodology, described in this work, to facilitate the process and assist in obtaining the optimal design.<br>El principal objectiu d'aquest treball és el disseny del BEta-deLayEd Neutron detector (BELEN) detector per FAIR (Facility for Antiproton Ion Research). El propòsit del detector és la mesura de les probabilitats d'emisió després de un beta-decay. El detector consiteix en un conjunt de 3He tubs envoltats per una matriu de polietilè. El diseny del detector ha estat desenvolupat mitjançant simulacions de Monte Carlo amb els programes MCNPX y GEANT4. Els objectius d'aquestes simulacions eren poden escollir les posicions dels tubs per obtenir una eficiencia máxima en la detecció de neutrons mantenint una eficiencia constant al llarg del rang d'energia esperat pels neutrons. Abans del disseny del detector per FAIR, hem desenvolupat el prototipus BELEN-20B amb 20 tubs i una eficiència mitjana pel rang d'energia fins a 2 MeV del 43% i el prototipus BELEN-30 amb 30 tubs i una eficiència mitjana pel rang d'energia fins a 2MeV del 38%. Per la caracterització del BELEN-30 s'ha fet servir una font de neutrons de 252Cf en el laboratori del GSI, on el detector BELEN va participar en un experiment fent servir la instal.lació FRS(Fragment Separator).

ANP; PETROBRAS, FINEP<br>Escoamentos multifásicos estão presentes não somente em diversos processos da natureza, mas também são muito comuns em diversas atividades industriais, como na exploração, produção e transporte de petróleo e gás. Na produção de petróleo, a mistura multifásica de gás, petróleo e água é frequentemente encontrada fluindo através de colunas e risers de produção. Nos últimos anos muito progresso no desenvolvimento e aplicação de técnicas de medição em escoamentos multifásicos foi realizado cujo intuito é quantificar com exatidão, prever e/ou controlar o fluxo de misturas multifásicas. Em especial técnicas de imageamento do escoamento multifásico estão em foco atualmente. Sensores de malha de eletrodos (wire-mesh sensors) são dispositivos que produzem imagens da distribuição das fases na seção transversal de uma tubulação com alta resolução espacial e temporal. Em estudos anteriores a utilização desse sensor é explorada em diversas aplicações em escoamentos bifásicos (predominantemente do tipo gás-líquido). O princípio de funcionamento do sensor é baseado na medição de uma única propriedade elétrica (condutividade ou permissividade) da mistura multifásica. Portanto, o objetivo deste trabalho é a aplicação da técnica wire-mesh para visualização de escoamentos multifásicos em alta velocidade para condições de escoamentos diferentes daquelas utilizados até o momento, bem como prover a técnica com melhorias, adicionando a capacidade de operar em dupla modalidade (medição simultânea condutiva/capacitiva). Assim, novos algoritmos e rotinas de processamento de dados para a investigação de escoamentos gás-líquido e sólido-líquido (suspensão) foram desenvolvidos e testados. A fim de continuar com o aprimoramento da técnica xiii de medição, uma nova eletrônica capaz de medir simultaneamente a permissividade e condutividade através da medição (vetorial) de amplitude e fase é introduzido. Além disso, um algoritmo baseado em um modelo da permissividade elétrica complexa realiza a fusão dos dados de condutividade e permissividade gerados pela técnica desenvolvida. Assim, esta fusão permite obter distribuições individuais das frações de fase de misturas de óleo-água-gás. A principal contribuição deste trabalho no campo de medição e investigação de escoamentos multifásicos é, por conseguinte, o desenvolvimento e aplicação soluções em software e processamento de dados para extração de parâmetros do fluxo multifasico a partir de dados do sensor wire-mesh, bem como a melhoria no sistema de medição com adoção de medidas vetoriais. Desta forma, a gama de aplicação do sensor wire-mesh é ampliada, permitindo a investigação de escoamentos gás-líquido e gás-sólido, assim como escoamentos trifásicos gás-líquido-líquido através de visualização em alta velocidade da distribuição de fases em escoamentos.<br>Multiphase flows are present not only in nature but also are very common in industrial activities such as in exploration, production and transport of oil and gas. In oil production, the mixture of gas, oil and water is often found streaming through production columns and flow risers. A lot of progress has been made in recent years in the development and application of measurement techniques applied to multiphase flow measurement in order to accurately quantify, predict and control the flow of multiphase mixtures. Especially, high-speed imaging of multiphase flows has received much attention in recent years. Wire-mesh sensors are flow-imaging devices and allow the investigation of multiphase flows with high spatial and temporal resolution. In the past, such sensors have found widespread application in gas-liquid flows. Its operating principle is based on measurement of a single electrical property (conductivity or permittivity) of flowing mixture. The objective of this work is the application of the wire-mesh technique for high-speed multiphase flow imaging in different flow conditions as applied so far, as well as the further development of this technique by adding the capability of dual-modality (simultaneous conductive/capacitive) operation. Hence, novel routines and data processing algorithms for the investigation of two-phase flows of the type gas-liquid and solid-liquid (slurry) were developed and tested. As a step towards the further development of the wire-mesh sensor technique, a novel dual- modality electronics being able to simultaneously evaluate the conductivity and permittivity component of a fluid through vector measurements (amplitude and phase) is introduced. Further, a model-based algorithm to fuse the data of dual-modality wire xi mesh sensor is developed to obtain individual phase fraction distributions in gas-oil- water three-phase flows. Hence, this thesis’ main contribution to the field of flow measurement and investigation is the development and application of software solutions for extracting flow parameters from wire-mesh sensor data, as well as the improvement in the hardware of measuring electronics. As a result, the range of application of wire-mesh sensors is enhanced being capable to investigate two-phase gas-liquid and slurry flows as well as gas-liquid-liquid three-phase flow problems through high-speed flow imaging.

This research develops three efficient textile flaw detection methods to facilitate automated textile inspection for the textile-related industries. Their novelty lies in detecting flaws with knowledge directly extracted from textile images, unlike existing methods which detect flaws with empirically specified texture features. The first two methods treat textile flaw detection as a texture classification problem, and consider that defect-free images of a textile fabric normally possess common latent images, called basis-images. The inner product of a basis-image and an image acquired from this fabric is a feature value of this fabric image. As the defect-free images are similar, their feature values gather in a cluster, whose boundary can be determined by using the feature values of known defect-free images. A fabric image is considered defect-free, if its feature values lie within this boundary. These methods extract the basis-images from known defect-free images in a training process, and require less consideration than existing methods on the degree of matching of a textile to the texture features specified for the textile. One method uses matrix singular value decomposition (SVD) to extract these basis-images containing the spatial relationship of pixels in rows or in columns. The alternative method uses tensor decomposition to find the relationship of pixels in both rows and columns within each training image and the common relationship of these training images. Tensor decomposition is found to be superior to matrix SVD in finding the basis-images needed to represent these defect-free images, because extracting and decomposing the tri-lateral relationship usually generates better basis-images. The third method solves the textile flaw detection problem by means of texture segmentation, and is suitable for online detection because it does not require texture features specified by experience or found from known defect-free images. The method detects the presence of flaws by using the contrast between regions in the feature images of a textile image. These feature images are the output of a filter bank consisting of Gabor filters with scales and rotations. This method selects the feature image with maximal image contrast, and partitions this image into regions with morphological watershed transform to facilitate faster searching of defect-free regions and to remove isolated pixels with exceptional feature values. Regions with no flaws have similar statistics, e.g. similar means. Regions with significantly dissimilar statistics may contain flaws and are removed iteratively from the set which initially contains all regions. Removing regions uses the thresholds determined by using Neyman-Pearson criterion and updated along with the remaining regions in the set. This procedure continues until the set only contains defect-free regions. The occurrence of the removed regions indicates the presence of flaws whose extents are decided by pixel classification using the thresholds derived from the defect-free regions. A prototype textile inspection system is built to demonstrate the automatic textile inspection process. The developed methods are proved reliable and effective by testing them with a variety of defective textile images. These methods also have several advantages, e.g. less empirical knowledge of textiles is needed for selecting texture features.<br>published_or_final_version<br>Industrial and Manufacturing Systems Engineering<br>Doctoral<br>Doctor of Philosophy

Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Physics, 2008.<br>Includes bibliographical references (p. 51).<br>Using the the SLIC simulator software and the org.lcsim reconstruction framework package, the performance of Mat Charles' NonTrivialPfa.java PFA for several different detector variations was found by determining the mass resolution for a given detector geometry. The variations tested included the layering of the hadronic calorimeter, the radius of the calorimeter, the interaction material utilized in the hadronic calorimeter and the type of read-out used in the calorimeter. Based on the performance of the PFA for the different variations, the optimal detector specifications for use with the PFA were discovered. The optimal detector was found to use scintillator as the sensitive layer and steel as the interaction material in the hadronic calorimeter. A general trend in increased performance with more layering was also observed for the calorimeter. Also illuminated in the study was the discovery of unexpected performance for radius variations.<br>by Lawrence Fernando Bronk.<br>S.B.