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Hauser, Mary. "Development and evaluation of a method to characterize the solubility of high-protein dairy powders using an ultrasonic flaw detector." Thesis, Kansas State University, 2015. http://hdl.handle.net/2097/20490.
Повний текст джерелаАнотація:
Master of ScienceFood Science Institute - Animal Sciences & Industry
Jayendra K. Amamcharla
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.
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Светличный, Виталий Анатольевич. "Резонансная вихретоковая дефектоскопия тонких неферомагнитных пленок". Thesis, Харьковский национальный университет радиоэлектроники, 2015. http://repository.kpi.kharkov.ua/handle/KhPI-Press/17672.
Повний текст джерелаАнотація:
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.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.
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Безкоровайный, Владимир Сергеевич. "Повышение помехоустойчивости феррозондовых дефектоскопов к магнитным полям помех". Thesis, Восточноукраинский национальный университет им. В. Даля, 2015. http://repository.kpi.kharkov.ua/handle/KhPI-Press/18964.
Повний текст джерелаАнотація:
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.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.
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Безкоровайний, Володимир Сергійович. "Підвищення перешкодостійкості ферозондових дефектоскопів до магнітних полів перешкод". Thesis, Друкарня "Фінвей", 2015. http://repository.kpi.kharkov.ua/handle/KhPI-Press/18960.
Повний текст джерелаАнотація:
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.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.
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Світличний, Віталій Анатолійович. "Резонансна вихрострумова дефектоскопія тонких неферомагнітних плівок". Thesis, НТУ "ХПІ", 2015. http://repository.kpi.kharkov.ua/handle/KhPI-Press/17663.
Повний текст джерелаАнотація:
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.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.
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Riego, Pérez Albert. "Design of the BELEN detector for wide energy range with flat and high detection efficiency." Doctoral thesis, Universitat Politècnica de Catalunya, 2016. http://hdl.handle.net/10803/396112.
Повний текст джерелаАнотація:
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.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).
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Santos, Eduardo Nunes dos. "Development and application of wire-mesh sensors for high-speed multiphase flow imaging." Universidade Tecnológica Federal do Paraná, 2015. http://repositorio.utfpr.edu.br/jspui/handle/1/1410.
Повний текст джерелаАнотація:
ANP; PETROBRAS, FINEPEscoamentos 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.
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.
8
Chandrasekar, Dhaarini. "AWS Flap Detector: An Efficient way to detect Flapping Auto Scaling Groups on AWS Cloud." University of Cincinnati / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1456848058.
Повний текст джерела
9
Tian, Xuwen, and 田旭文. "Data-driven textile flaw detection methods." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2012. http://hdl.handle.net/10722/196091.
Повний текст джерелаАнотація:
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.published_or_final_version
Industrial and Manufacturing Systems Engineering
Doctoral
Doctor of Philosophy
10
Bronk, Lawrence Fernando. "Particle detector optimization via particle flow algorithms." Thesis, Massachusetts Institute of Technology, 2008. http://hdl.handle.net/1721.1/44465.
Повний текст джерелаАнотація:
Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Physics, 2008.Includes bibliographical references (p. 51).
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.
by Lawrence Fernando Bronk.
S.B.
11
曾偉明 and Wai-ming Peter Tsang. "Computer aided ultrasonic flaw detection and characterization." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1987. http://hub.hku.hk/bib/B31231007.
Повний текст джерела
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Tsang, Wai-ming Peter. "Computer aided ultrasonic flaw detection and characterization /." [Hong Kong : University of Hong Kong], 1987. http://sunzi.lib.hku.hk/hkuto/record.jsp?B12344928.
Повний текст джерела
13
Blaiklock, Philip. "A portable, wireless inductive-loop vehicle counter." Thesis, Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/34737.
Повний текст джерелаАнотація:
This thesis descries the evolution and testing of a fully portable, inductive loop vehicle counter system. As a component of the NFS Embedded Distributed Simulation for Transportation System Management project, the system's cellular modem transmits real-time data to servers at Georgia Institute of Technology. From there, the data can be fed into simulations predicting travel behavior. Researchers revised both the detector circuit, and the temporary, reusable loop pad several times over multiple rounds of field testing.
The final tested version of this system demonstrates the efficacy of uncommonly small
inductive loops. When paired with a reliable data transmission channel, the system was
shown to capture nearly 96% of actual through traffic.
14
Gimbert, Norman Wesley II. "Development of a Sensor for Inflight Detection of Three-Dimensional Flow Separation on a Wing." Thesis, Virginia Tech, 1997. http://hdl.handle.net/10919/36987.
Повний текст джерелаАнотація:
A real need exists for a sensor capable of detecting flow-field separation on an airplane
wing during routine flight operations. A sensor of this type could lead to both improved
flight safety and increased performance. It would also contribute to future separation
control technologies. A new idea is presented for a sensor that is cost effective, easy to
maintain, durable, and highly effective. The system, known as a Thermal Grid, works by
using a grid of heaters and temperature sensors to trace out the streamlines closest to the
surface. Specific singularities in these streamlines are excellent indicators of flow
separation. This paper addresses many of the necessary principles that are necessary to
making the Thermal Grid an operational device. An analytic design is presented that
details the system requirements and potential performance, including heater/sensor
spacing, heater power requirements, sensor time response and sensitivity needs and the
effects of changes in flow conditions.Master of Science
15
Patyk, Rodolfo Luiz. "Instrumentação baseada em redes de Bragg em fibra ótica para a monitoração da vazão de fluídos através do uso da termometria." Universidade Tecnológica Federal do Paraná, 2010. http://repositorio.utfpr.edu.br/jspui/handle/1/1342.
Повний текст джерелаАнотація:
Neste trabalho foi inferida a vazão de um fluido que escoava em um tubo de cobre através do uso da termometria em diferentes regimes de escoamento, com o uso de sensores óticos de temperatura baseados em redes de Bragg escritas em fibras óticas (FBG). Foi utilizado um processo de medição não-intrusivo de vazão através do uso da termometria o qual consiste no monitoramento da temperatura em dois pontos fixos, com uma distância conhecida (d), na parede externa do tubo. Além dos sensores óticos de temperatura foram utilizados sensores comerciais de temperatura, termopares, com a intenção de comparar os resultados obtidos experimentalmente. No experimento o fluido estará escoando com uma temperatura T1, e em determinado tempo será liberado um pequeno volume de fluido com temperatura T2, onde T2 > T1, simulando um pulso térmico. É monitorada a evolução temporal do pulso térmico e anotado o tempo de trânsito (t) entre os dois sensores de temperatura. Com o valor da distância (d) e o tempo de trânsito (t) obtemos a velocidade média de escoamento (v). De posse da (v) e área de seção transversal do tubo (A) podemos inferir a vazão. A técnica de medição não-intrusiva de vazão através do uso da termometria foi testada para diferentes regimes de escoamento: laminar, transição e turbulento. Foram comparados os valores medidos da vazão mássica do sistema com os valores obtidos experimentalmente para os sensores comerciais e redes de Bragg. Para o regime turbulento a exatidão de medição da velocidade de escoamento do fluido foi de 0,75 para os sensores óticos e 0,60 para os sensores comerciais. No caso do regime de transição a exatidão na medida foi de 0,90 para o sensor ótico e 0,69 para os sensores comerciais. Finalmente para o regime laminar a exatidão nas medidas foram [sic] de 0,98 para os sensores ótico [sic] e 0,76 para os sensores comerciais.In this work we inferred a fluid flow seeping from a cooper pipe through thermometers scheme in different flows, through the use of optical sensors based on temperature Bragg Gratings written in optical fiber (FBG). We used a non-intruse measurement process through the use of thermometry, which consists of monitoring the temperature at two fixed points with a know distance (d) on the outer wall of the tube. Besides the optical sensors of temperature, sensors were used for commercial temperature, thermocouples, with the objective of comparing the results obtained experimentally. In the experiment, the fluid is flowing at a temperature T1, and will be released at any given time a small volume of fluid with temperature T2, were T2 > T1, simulating a thermal pulse. It's monitored the evolution of the thermal pulse and noted the transit time (t) between the two temperature sensors. With the value of distance (d) and transit time (t) we obtain the average velocity of flow (v). Tenure velocity (v) and the tube transversal sectional area (A) we can infer the non-intrusive measurement technique flow. The flow though the use of thermometry was tested for different flow regimes: laminar, transitional and turbulent. We compared the values measured with the mass flow of the system with the experimental values for the sensors and commercial FBG's. In the turbulent the accuracy of measuring the speed and fluid flow was 0.75 to 0.60 optical sensors and sensor for commercial purposes. Finally for the laminar accuracy in the measurements were 0.98 optical sensors and 0.76 for commercial sensors.
16
Zhang, Xu. "A numerical and experimental study of a dynamic resonant shear stress sensor." Laramie, Wyo. : [University of Wyoming], 2006. http://proquest.umi.com/pqdweb?did=1221706921&sid=1&Fmt=2&clientId=18949&RQT=309&VName=PQD.
Повний текст джерела
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Chan, Lok-sang, and 陳樂生. "Adaptive flow detector and estimator for ultrasound high frame rate vector flow imaging." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2011. http://hub.hku.hk/bib/B47753043.
Повний текст джерелаАнотація:
Cardiovascular diseases is a leading cause of death worldwide and improvement of the
corresponding screening tool is the best way to deal with this clinical problem. In this thesis
we attempted to develop a framework of ultrasound high frame rate vector flow imaging
(VFI) by emphasizing on the design of corresponding flow detector and flow estimator. We
believe that the high temporal resolution and the complex blood flow visualization ability of
high frame rate VFI enables it to be further developed as a reliable flow imaging modality
for cardiological examination.
In order to achieve high temporal resolution, fast data acquisition algorithm was applied
in the framework. Doppler signals acquired using this acquisition algorithm have two
unique characteristics comparing with conventional data acquisition algorithm: (1) widen
spectral bandwidth and (2) greater clutter to blood signal ratio. These signal characteristics
give rise to unique signal processing. In addition, complex blood flow pattern, which
is common in cardiological examination, induces extra challenges in implementing high
frame rate VFI. In this thesis, flow detector which is adaptive to different flow scenarios
and high dynamic range 2D flow estimator were presented.
The proposed flow detector employes K-means++ clustering algorithm to classify clutter
components from acquired Doppler signals. As a performance analysis, Field II simulation
studies were performed by a parabolic flow phantom (flow velocity: 10mm/s to
200mm/s; tissue motion: 10mm/s; beam-flow angle: 60?). The post-filtered Doppler power
map and BCR were used as qualitative and quantitativemeasures of detectors performance.
Analyzed result has indicated that, as compared with clutter downmixing detector and
eigen-based detector, the proposed flow detector could classify and suppress clutter component
more effectively. Results also suggested that the proposed flow detector is more
adaptive to slow flow scenarios where existing flow detectors failed to distinguish between
blood and clutter components.
For the proposed flow estimator, it was characterized by the interpolation of speckle
tracking results in Lagrangian reference frame. The estimation bias and RMS error were
calculated for different flow scenarios (flow velocity: 100mm/s to 500mm/s; beam-flow
angle: 15? to 60?). It was found that the proposed flow estimator provides higher dynamic
range than conventional speckle tracking-based flow estimator. Nonetheless, it is also observed
that the estimation variances and errors increases in slow flow scenarios.
In order to demonstrate the medical potential of the proposed high frame rate VFI
framework. A carotid bifurcation simulation model with realistic blood flow pattern calculated
using computational fluid dynamic software was applied in the performance evaluation
study. In the VFI image obtained, complex blood flow pattern was readily visualized.
In contrast, conventional ultrasound flow imaging was only able to estimate axial velocity
map and thus lead to many ambiguities in analyzing the complex blood flow pattern. It
proved that ultrasound high frame rate VFI has the potential to be further developed into a
new cardiological examination technique.published_or_final_version
Electrical and Electronic Engineering
Master
Master of Philosophy
18
Liu, Ying. "Outlier detection by network flow." Birmingham, Ala. : University of Alabama at Birmingham, 2007. https://www.mhsl.uab.edu/dt/2007p/liu-ying.pdf.
Повний текст джерелаАнотація:
Thesis (Ph. D.)--University of Alabama at Birmingham, 2007.Additional advisors: Elliot J. Lefkowitz, Kevin D. Reilly, Robert Thacker, Chengcui Zhang. Description based on contents viewed Feb. 7, 2008; title from title screen. Includes bibliographical references (p. 125-132).
19
Ayichiluhm, Theodros, and Vivek Mohan. "IPv6 Monitoring and Flow Detection." Thesis, Blekinge Tekniska Högskola, Sektionen för datavetenskap och kommunikation, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-4165.
Повний текст джерелаАнотація:
IPv6 Privacy extensions, implemented in major operating systems, hide user’s identity by using a temporary and a randomly generated IPv6 addresses rather than using the former, EUI-64 format where the MAC address is part of the IPv6 address. This solution for privacy has created a problem for network administrators to back-trace an IPv6 address to a specific MAC address, since the temporary IP address used once by the node is removed from the interface after a period of time. An IPv6 Ethernet test bed is setup to investigate IPv6 implementation dynamics in Windows 7 and Ubuntu10.04 operating systems. The testbed is extended to investigate the effects of temporary IPv6 addresses due to IPv6 privacy extensions on the on-going sessions of different applications including ping, File Transfer Protocol (FTP) and video streaming (HTTP and RTP). On the basis of the knowledge obtained from investigations about dynamics of IPv6 privacy extensions, this work proposes Internet Protocol version 6 Host Tracking (IPv6HoT), a web based IPv6 to MAC mapping solution. IPv6HoT uses Simple Network Management Protocol (SNMP) to forward IPv6 Neighbor table from routers to Network Management Stations (NMS). This thesis work provides guidelines for configuring IPv6 privacy extensions in Ubuntu10.04 and Windows 7; the difference of implementation between these two operating systems is also presented in this work. The results show that temporary IPv6 addressing has a definite effect on the on-going sessions of video streaming and FTP applications. Applications running as server on Temporary IPv6 address encountered more frequent on-going session interruptions than applications running as a server over public IPv6 address. When temporary IPv6 addresses were configured to host FTP and video streaming applications, their on-going sessions were permanently interrupted. It is also observed that LFTP, a client FTP application, resumes an interrupted session.theodrosmek11@gmail.com, iamvivek86@gmail.com
20
Zhang, Xiaoping. "Improved system for collecting real-time truck data from dual-loop detectors /." Thesis, Connect to this title online; UW restricted, 2004. http://hdl.handle.net/1773/10162.
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21
O'Connell, Gregory Raymond. "Detector cell hydrodynamics and electrode selectivity in flow-injection potentiometry." Thesis, Brunel University, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.290935.
Повний текст джерела
22
Johnson, Marcus James. "Pulsed eddy-current measurements for materials characterization and flaw detection." Thesis, University of Surrey, 1997. http://epubs.surrey.ac.uk/966/.
Повний текст джерела
23
Afrooz, mehr Mohammad, and Maziar Haghpanah. "Optical Flow Features for Event Detection." Thesis, Högskolan i Halmstad, Sektionen för Informationsvetenskap, Data– och Elektroteknik (IDE), 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-25016.
Повний текст джерелаАнотація:
In this thesis, we employ optical flow features for the detection of the rigid or non‐rigid single object on an input video. For optical flow estimation, we use the Point Line [PL] method [2] (as a local method) to estimate the motion of the image sequence which is generated from the input video stream. Although the Lukas and Kanade [LK] is a popular local method for estimation of the optical flow, it is weak in dealing with the linear symmetric images even by use of regularization [e.g. Tikhonov]. The PL method is more powerful than the LK method and can properly separate both line flow and point flow. For dealing with rapidly changing data in some part of an image (high motion problem), a gaussian pyramid with five levels (different image resolutions) is employed. In this way, the pyramid height (Level) must be chosen properly according to the maximum optical flow that we expect in each section of the image without iteration. After determining the best‐estimated optical flow vector for every pixel, the algorithm should detect an object on video with its direction to the right or left. By using techniques such as segmentation and averaging the magnitude of flow vectors the program can detect and distinguish rigid objects (e.g. a car) and non‐rigid objects (e.g. a human). Finally the algorithm makes a new video output that includes detected object with flow vectors, the pyramid levels map which has been used for optical flow estimation and a respective binary image.
24
Almatrafi, Mohammed Mutlaq. "Optical Flow for Event Detection Camera." University of Dayton / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1576188397203882.
Повний текст джерела
25
Nawawi, Mustaffa bin. "Flow injection analysis with bioluminescence detection." Thesis, Loughborough University, 1987. https://dspace.lboro.ac.uk/2134/31964.
Повний текст джерелаАнотація:
The detection of bacterial contamination of water, pharmaceutical products etc. is of great importance, and is most conveniently performed by the detection of bacterial ATP (Adenosine TriPhosphate) using the luciferin-luciferase bioluminescence system. This system uses unstable and expensive reagents, and emits transient light signals. In this study an FIA (Flow Injection Analysis) system was set up to monitor the light signal produced by the reaction. Using a luminometric detector (a liquid scintillation counter) with the FIA system, the reaction length, sample volume, flow rates, pH etc. were investigated.
26
Bakolias, Charalampos. "Oblique imaging of scattered light for surface inspection." Thesis, Imperial College London, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.246154.
Повний текст джерела
27
Miller, Keith Edward. "Dynamic surface tension detector in flow injection analysis and liquid chromatography /." Thesis, Connect to this title online; UW restricted, 2000. http://hdl.handle.net/1773/8506.
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28
Song, Kyle Seregay. "Two-Phase Flow Measurement using Fast X-ray Line Detector System." Diss., Virginia Tech, 2019. http://hdl.handle.net/10919/103371.
Повний текст джерелаАнотація:
Void fraction is an essential parameter for understanding the interfacial structure, and heat and mass transfer mechanisms in various gas-liquid flow systems. It becomes critically important to accurately measure void fraction as advanced high fidelity two-phase flow models require high-quality validation data. However, void fraction measurement remains a challenging task to date due to the complexity and rapid-changing characteristic of the gas-liquid boundary flow structure. This study aims to develop an advanced void fraction measurement system based on x-ray and fast line detector technologies. The dissertation has covered the major components necessary to develop a complete measurement system. Spectral analysis of x-ray attenuation in two-phase flow has been performed, and a new void fraction model is developed based on the analysis. The newly developed pixel-to-radial conversion algorithm is capable of converting measured void fraction along with the detector array to the radial distribution in a circular pipe for a wide range of void fraction conditions. The x-ray system attains the radial distributions of key measurable factors such as void fraction and gas velocity. The data are compared with the double-sensor conductivity probe and gas flowmeter for various flow conditions. The results show reasonable agreements between the x-ray and the other measurement techniques. Finally, various 2-D tomography algorithms are implemented for the non-axisymmetric two-phase flow reconstruction. A comprehensive summary of classical absorption tomography for the two-phase flow study is provided. An in-depth sensitivity study is carried out using synthetic bubbles, aiming to investigate the effect of various uncertainty factors such as background noise, off-center shift, void profile effect, etc. The sensitivity study provides a general guideline for the performance of existing 2-D reconstruction algorithms.Doctor of Philosophy
Gas-liquid flow phenomenon exists in an extensive range of natural and engineering systems, for example, hydraulic pipelines in a nuclear reactor, heat exchanger, pump cavitation, and boilers in the gas-fired power stations. Accurate measurement of the void fraction is essential to understand the behaviors of the two-phase flow phenomenon. However, measuring void fraction distribution in two-phase flow is a difficult task due to its complex and fast-changing interfacial structure. This study developed a comprehensive suite of the non-intrusive x-ray measurement techniques, and a pixel-to-radial conversion algorithm to process the line- and time-averaged void fraction information. The newly developed algorithm, called the Area-based Onion-Peeling (ABOP) method, can convert the pixel measurement to the radial void fraction distribution, which is more useful for studying and modeling axisymmetric flows. Various flow conditions are measured and evaluated for the benchmarking of the algorithm. Finally, classical 2-D reconstruction algorithms are investigated for the void fraction measurement in non-axisymmetric flows. A comprehensive summary of the performance of these algorithms for a two-phase flow study is provided. An in-depth sensitivity study using synthetic bubbles has been performed to examine the effect of uncertainty factors and to benchmark the algorithms for the non-axisymmetric flows.
29
Maschio, Maria Celeste. "Performance evaluation of detector for digital radiography." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amslaurea.unibo.it/8317/.
Повний текст джерелаАнотація:
Lo scopo di questo lavoro è la caratterizzazione fisica del flat panel PaxScan4030CB Varian, rivelatore di raggi X impiegato in un ampio spettro di applicazioni cliniche, dalla radiografia generale alla radiologia interventistica.
Nell’ambito clinico, al fine di una diagnosi accurata, è necessario avere una buona qualità dell’immagine radiologica mantenendo il più basso livello di dose rilasciata al paziente.
Elemento fondamentale per ottenere questo risultato è la scelta del rivelatore di radiazione X, che deve garantire prestazioni fisiche (contrasto, risoluzione spaziale e rumore) adeguati alla specifica procedura. Le metriche oggettive che misurano queste caratteristiche sono SNR (Signal-to-Noise Ratio), MTF (Modulation Transfer Function) ed NPS (Noise Power Spectrum), che insieme contribuiscono alla misura della DQE (Detective Quantum Efficiency), il parametro più completo e adatto a stabilire le performance di un sistema di imaging. L’oggettività di queste misure consente anche di mettere a confronto tra loro diversi sistemi di rivelazione.
La misura di questi parametri deve essere effettuata seguendo precisi protocolli di fisica medica, che sono stati applicati al rivelatore PaxScan4030CB presente nel laboratorio del Centro di Coordinamento di Fisica Medica, Policlinico S.Orsola.
I risultati ottenuti, conformi a quelli dichiarati dal costruttore, sono stati confrontati con successo con alcuni lavori presenti in letteratura e costituiscono la base necessaria per la verifica di procedure di ottimizzazione dell’immagine radiologica attraverso interventi sul processo di emissione dei raggi X e sul trattamento informatico dell’immagine (Digital Subtraction Angiography).
30
Čermák, Peter. "Vyhodnocení vlivu výkonu vývěv na proudění plynu ve scintilačním detektoru s ohledem na funkčnost." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2011. http://www.nusl.cz/ntk/nusl-219067.
Повний текст джерелаАнотація:
The work is devoted to problems of electron microscopy, focusing on the scintillation detector, which is located in chamber separating the field from different pressures. Using of the CAD and CAE was created 3D model of the detector, which took place on calculations focused to influence of the performance of different types of air pumps at gas flow between the chambers. The results of individual variants are compared in graphic form and evaluated.
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McConney, Michael Edward. "Learning and applying material-based sensing lessons from nature." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/29749.
Повний текст джерелаАнотація:
Thesis (Ph.D)--Polymer, Textile and Fiber Engineering, Georgia Institute of Technology, 2010.Committee Chair: Tsukruk, Vladimir; Committee Member: Shofner, Meisha; Committee Member: Srinivasarao, Mohan; Committee Member: Thio, Yonathan; Committee Member: Weissburg, Marc. Part of the SMARTech Electronic Thesis and Dissertation Collection.
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Wolf, Katharine. "Flow injection analysis with photodiode array detection." Thesis, University of Hull, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.278427.
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Beattie, P. "The effect of debonding in fibre-reinforced composites on ultrasonic backscattering." Thesis, University of Surrey, 1992. http://epubs.surrey.ac.uk/843471/.
Повний текст джерелаАнотація:
The work presented in this thesis concerns the problem of detecting and characterising the effect of fibre-matrix debonds in a fibre-reinforced composite, on ultrasonic backscattering. Theoretical and experimental investigations were conducted into this problem. Three mathematical models were examined. The first assumed that the debond was a thin crack with non-contacting faces surrounding the fibre. The second modelled the debond by allowing tangential slip between the matrix and fibre defined by an effective shear modulus, K. For the third model, the debond was approximated by a thin visco-elastic layer separating the matrix and fibre. The results of the modelling suggested that for an incident longitudinal wave, the first model acts as an air-filled void with a sharp resonance present in the low ka region. The second and third models both show the backscattering to be attenuated. Experimental investigations were carried out on scale models of a single fibre embedded in an araldite matrix. Steel or copper wires were used for the reinforcing fibre. The agreement between theory and experiment for a well-bonded wire was excellent. The effect on the longitudinal backscattered wave of the wire immediately after debonding was to attenuate heavily the resonances in the backscatter form function. However, after approximately an hour the scatter is seen to relax, closely resembling that from a well-bonded wire. In view of the only partial ability of longitudinal incident waves to detect debonds, shear wave (SH) incidence was investigated. It was shown that shear waves were far more sensitive to the presence of fibre-matrix debonds.
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Hallam, Robert Kenneth. "Dual optical detection and multivariate analysis." Thesis, Loughborough University, 2003. https://dspace.lboro.ac.uk/2134/33747.
Повний текст джерелаАнотація:
The application of flow injection analysis into the simultaneous determination of two or more components has been challenging for many years. Various detectors such as ultraviolet/visible absorption, fluorescence, and electrochemical detectors, have been used individually or in combination with each other. Combining two optical detectors such as fluorescence and ultraviolet/visible absorbance, however, has always been challenging due to their incompatibilities. However, the recent developments in fibre optics, solid-state light sources and miniaturised charged coupled devices (CCD), allow novel designs and most of the incompatibilities be circumvented. A flow injection manifold can now be adapted so that only one flow cell is used along with a diode array CCD detector that can detect both fluorescence and absorbance simultaneously. The initial development and testing of such dual detection system is described in this thesis.
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Robertson, Andrew J. "Extended surface flow and heat transfer studies." Thesis, University of Oxford, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.302219.
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Gwenlan, Claire. "Jets and energy flow in photoproduction using the ZEUS detector at HERA." Thesis, University College London (University of London), 2004. http://discovery.ucl.ac.uk/1446606/.
Повний текст джерелаАнотація:
The hard photoproduction of jets has been studied using the ZEUS detector at HERA. The data were collected during the 1996-1997 e+p running period and correspond to an integrated luminosity of 38.6 pb-1. Events were selected with a photon-proton centre-of-mass energy in the range 134 W7P 277 GeV with photon virtualities of Q2 1 GeV2. Jets were defined using the longitudinally invariant k algorithm in the inclusive mode. Cross sections for the photoproduction of four high transverse energy jets have been measured. This is the highest order process in QCD to have been studied at HERA to date. Two kinematic regions have been defined: the inclusive and the high mass samples. The high mass sample contains only events with a four jet invariant mass satisfying m.;j 50 GeV. The data axe compared to parton shower models which resum leading logarithms to produce multi-parton final states. The inclusive distributions are found to be very sensitive to the underlying event model. Models with no simulation of the underlying event are unable to describe the shape of the distributions. Inclusion of only a soft underlying event is also disfavoured. However, the description of the data is significantly improved by inclusion of multi-parton interactions, which introduces a hard, partonic scattering component to the underlying event. The high mass cross sections are well described by the parton shower models and are relatively insensitive to the underlying event model and, consequently, are considered suitable for comparison with fixed order perturbative QCD calculations when they become available. The rate of four jet photoproduction, relative to that of three jet, shows an excess over the predictions of models which use only initial- and final-state QCD radiation to produce multi-parton final states. The data can be described by models including multi- parton interactions, which provides an additional mechanism for the production of four jets. The data from this analysis have also been used to provide constraints on the parton shower model parameters. Cross sections for the photoproduction of two jets separated by a large region in rapidity have been measured. Rapidity gap events are defined in terms of the energy flow in the region between the two highest transverse energy jets. Gap fractions, defined as the ratio of the two jet gap cross sections to the two jet inclusive cross sections, have also been measured. An excess of events with a rapidity gap, over that expected from standard QCD, is observed. This can be interpreted as evidence for the exchange of a strongly interacting colour singlet object. The data are well described by the leading logarithmic approximation BFKL pomeron with a choice of c.;re' = af271' = 0.18 and UJQ = 0.48. Taking into account the constraints imposed on the underlying event model from the multi-jets analysis, an estimate of S = 65 - 70% has been estimated for the gap survival probability.
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Brygoo, Stephanie. "X-ray lateral migration radiography non destructive flaw detection measurements and simulations." [Gainesville, Fla.] : University of Florida, 2002. http://purl.fcla.edu/fcla/etd/UFE1000110.
Повний текст джерелаАнотація:
Thesis (M.S.)--University of Florida, 2002.Title from title page of source document. Document formatted into pages; contains xii, 91 p.; also contains graphics. Includes vita. Includes bibliographical references.
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Zheng, Jianyang. "Measuring signalized intersection performances with traffic sensors /." Thesis, Connect to this title online; UW restricted, 2008. http://hdl.handle.net/1773/10190.
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Mao, Jialei. "Automatic system to measure turning movement and intersection delay." Akron, OH : University of Akron, 2009. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=akron1239638295.
Повний текст джерелаАнотація:
Thesis (M.S.)--University of Akron, Dept. of Civil Engineering, 2009."May, 2009." Title from electronic thesis title page (viewed 8/2/2009) Advisor, Ping Yi; Committee members, William H. Schneider IV, Anil Patnaik; Department Chair, Wieslaw K. Binienda; Dean of the College, George K. Haritos; Dean of the Graduate School, George R. Newkome. Includes bibliographical references.
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Cheng, Sau Kuen. "Real-time optical fibre sensing of phytoplankton for studies in size distribution and concentration." HKBU Institutional Repository, 1996. http://repository.hkbu.edu.hk/etd_ra/56.
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Himsworth, John M. "Linear array CMOS detectors for laser Doppler blood flow imaging." Thesis, University of Nottingham, 2011. http://eprints.nottingham.ac.uk/12392/.
Повний текст джерелаАнотація:
Laser Doppler blood flow imaging is well established as a tool for clinical research. The technique has considerable potential as an aid to diagnosis and as a treatment aid in a number of situations. However, to make widespread clinical use of a blood flow imager feasible a number of refinements are required to make the device easy to use, accurate and safe. Existing LDBF systems consist of 2D imaging systems, and single point scanning systems. 2D imaging systems can offer fast image acquisition time, and hence high frame rate. However, these require high laser power to illuminate the entire target area with sufficient power. Single point scanning systems allow lower laser power to be used, but building up an image of flow in skin requires mechanical scanning of the laser, which results in a high image acquisition time, making the system awkward to use. A new approach developed here involves scanning a line along a target, and imaging the line with a 1D sensor array. This means that only one axis of mechanical scanning is required, reducing the scanning speed, and the laser power is vastly reduced from that required for a 2D system. This approach lends itself well to the use of integrated CMOS detectors, as the smaller pixel number means that a linear sensor array can be implemented on an IC which has integrated processing while keeping overall IC size, and hence cost, lower than equivalent 2D imaging systems. A number of front-end and processing circuits are investigated in terms of their suitability for this application. This is done by simulating a range of possible designs, including several logarithmic pixels, active pixel sensors and opamp-based linear front-ends. Where possible previously fabricated ICs using similar sensors were tested in a laser Doppler flowmetry system to verify simulation results. A first prototype IC (known as BVIPS1) implements a 64x1 array of buffered logarithmic pixels, chosen for their combination of sufficient gain and bandwidth and compact size. The IC makes use of the space available to include two front-end circuits per pixel, allowing other circuits to be prototyped. This allows a linear front-end based on opamps to be tested. It is found that both designs can detect changes in blood flow despite significant discrepancies between simulated and measured IC performance. However, the signal-noise ratio for flux readings is high, and the logarithmic pixel array suffers from high fixed pattern noise, and noise and distortion that makes vein location impossible. A second prototype IC (BVIPS2) consists of dual 64x1 arrays, and integrated processing. The sensor arrays are a logarithmic array, which addresses the problems of the first IC and uses alternative, individually selectable front-ends for each pixel to reduce fixed-pattern noise, and an array of opamp-based linear detectors. Simulation and initial testing is performed to show that this design operates as intended, and partially overcomes the problems found on the previous IC - the IC shows reduced fixed pattern noise and better spatial detection of blood flow changes, although there is still significant noise.
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Crawford, Carolin Susan. "The detection of distant cooling flows." Thesis, University of Cambridge, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.293490.
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Martin, Peter Terence. "Urban traffic movement prediction from automatic flow detection." Thesis, University of Nottingham, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.334986.
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Steinkraus, Kurt Alan 1978. "Optical flow for obstacle detection in mobile robots." Thesis, Massachusetts Institute of Technology, 2001. http://hdl.handle.net/1721.1/86783.
Повний текст джерелаАнотація:
Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2001.Includes bibliographical references (p. 65-66).
by Kurt Alan Steinkraus.
S.M.
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Adefila, Kehinde. "Flow measurement and leakage detection of gaseous CO2." Thesis, University of Kent, 2015. https://kar.kent.ac.uk/49162/.
Повний текст джерелаАнотація:
In order to combat the climate change caused by increasing emissions of CO2 from industrial processes, Carbon Capture and Storage (CCS) technologies have been accepted worldwide to address these pressing global warming concerns. So as to efficiently manage material and financial losses across the entire stream, accurate accounting and monitoring through fiscal metering of CO2 in CCS transportation pipelines are core and required features for the deployment of CCS technologies. Moreover, these technical requirements are part of the legal compliance schemes and guidelines from various regulatory bodies. This thesis reports experimental studies of two different metering technologies, an Averaging Pitot Tube (APT) and a Coriolis mass flowmeter (CMF), for CO2 flow measurement, together with the design and implementation of a CO2 flow calibration facility. A prototype system for the leak detection of the gas phase of CO2 is also developed. A review of the methodologies and technologies for the flow measurement and leak detection of CO2 gas is firstly given, followed by the discussion of the main challenges and technical requirements in their applications. Based on this review, two flow metering technologies, APT and CMF, are selected for experimental studies and a calibration platform using both volumetric and direct mass measurement methods for the gas phase of CO2 is also developed. The APT and CMF were calibrated and evaluated in the test facility. Experimental results obtained in this test facility demonstrate that the instruments are capable of accurately metering gaseous CO2 within a measurement uncertainty of ±1.5%. Flow characterization of the fluid under wet and mixed components conditions were further assessed with both meters. Under wet CO2 flow, results obtained show that both flow instruments are subject to significant measurement errors. The APT gave an error of up to ±25%, for a liquid fraction of 20%, while the error of the CMF was up ±6%, for a liquid fraction of 10%. Further investigations show that these errors can, however, be corrected through simple and straightforward algorithms that can be easily incorporated into computing processes in the flowmeters. In binary gaseous mixture tests, the CMF proved to be very reliable in the gas combination processes and likewise in the metering of the CO2 mixture (≤ ±1%), while a higher degree of uncertainty was registered for the APT (≤ ±4%). Overall analyses from investigations confirmed the APT and CMF instruments as promising technologies for CO2 flow measurement and can be further improved for application in actual CCS conditions. In addition, this thesis describes experimental investigations of the leak detection of CO2 gas from a pipeline, with emphasis on full controllability and flexibility of the operational process. An imaging system using passive temperature change detection techniques is designed, implemented and evaluated. The effectiveness of the developed technique is examined on a laboratory-scale flow rig system. Results obtained from tests confirmed the operability of the system configuration and validation of the thermal imaging approach. Suggestions for future development and enhancement of the proposed techniques are finally given.
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Black, Richard Allyn. "A flush mounted microelectromechanical system (MEMS) pressure and flow sensor based air data system /." Thesis, Connect to this title online; UW restricted, 1999. http://hdl.handle.net/1773/10012.
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Singh, Rohitendra Kumar. "A study of air flow in a network of pipes used in aspirated smoke detectors." full-text, 2009. http://eprints.vu.edu.au/15172.
Повний текст джерелаАнотація:
Thesis (M. Eng.)--Victoria University (Melbourne, Vic.), 2009.Submitted in fulfilment of the requirements for the degree of Master of Engineering in Mechanical Engineering. Includes bibliographical references.
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Galdiano, Eder dos Santos. "Contribuição ao estudo de um medidor não-invasivo da espessura da camada de agua em um escoamento anular oleo-agua." [s.n.], 2010. http://repositorio.unicamp.br/jspui/handle/REPOSIP/263304.
Повний текст джерелаАнотація:
Orientadores: Leonardo Goldstein Junior, Emerson dos ReisDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica
Made available in DSpace on 2018-08-15T08:49:00Z (GMT). No. of bitstreams: 1 Galdiano_EderdosSantos_M.pdf: 3731509 bytes, checksum: 5415460955079bfdf8773ebcc4ee6500 (MD5) Previous issue date: 2010
Resumo: Esse trabalho é uma contribuição ao estudo de uma sonda não-intrusiva para medição da espessura da camada anular de escoamentos bifásicos óleo-água - core-flow. É discutida a construção do sensor capacitivo da sonda. Dela são avaliados o desempenho estático, numa bancada construída para este fim, e o dinâmico na presença de escoamento numa bancada existente no Laboratório de Petróleo (LabPetro). Através dos testes estáticos, foram obtidas informações sobre a resposta da sonda: formato da curva de resposta, sensibilidade, faixa de medição, e estudou-se o efeito da condutividade da água. Os dados experimentais foram comparados com resultados de simulação numérica obtidos por outro autor. Nos testes dinâmicos, foi utilizada uma técnica de medição da espessura da camada de água através de imagens de filmagens registradas do escoamento, sendo que estes dados foram comparados com os obtidos com a sonda capacitiva, assim permitindo a avaliação do seu desempenho no escoamento. Os resultados demonstram potencial do sistema proposto, mas também apontam para a necessidade de novos estudos e aperfeiçoamentos
Abstract: This work is a contribution to the study of a non-intrusive probe for measurement of the thickness of the water layer of a core-annular flow. A capacitive probe was built and its static performance was evaluated from tests executed in a specially designed bench-scale apparatus. In addition, evaluation of the dynamic performance was made possible from fluid-flow tests in a multiphase flow loop. From the static tests information was obtained about the probe output: shape of the produced response, sensitivity, range and the water electrical conductivity effect. The experimental data were compared with results of a numerical simulation available from a different author. In the dynamic tests the measurement technique used to obtain the thickness of the annular water layer consisted of a sequence of photographic images from a fast camera. The results were compared with those from the capacitive probe, allowing the evaluation of its performance in the presence of fluid flow. The results demonstrate the potential of the considered system, but they also point out to the necessity of new studies and development
Mestrado
Termica e Fluidos
Mestre em Engenharia Mecânica
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Rojas, Benitez Angélica. "El flow peluquería estilo Dominicano. Propuesta metodológica para detectar indicios identitarios." Tesis, Universidad de Chile, 2015. http://repositorio.uchile.cl/handle/2250/139473.
Повний текст джерелаАнотація:
Memoria para optar al título de Diseñador GráficoChile se ha caracterizado por ser un país migratorio. Durante el último siglo, ha aumentado considerablemente el número de inmigrantes, siendo Santiago una de las ciudades más receptivas.En los últimos años, la inmigración dominicana en Chile se ha presentado como una de las que más ha aumentado. Por lo cual nace el interés por indagar la cultura dominicana en Chile en su vida cotidiana.El presente proyecto propone una metodología multidisciplinar con un enfoque principalmente de diseño, para detectar mediante la frontera cultural entre los dominicanos y chilenos, indicios de una identidad presentes en el entorno cotidiano de la peluquería “El Flow”.
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Anam, Onditi Ouma. "Gas diffusion-flow injection interfaces for mass spectrometric and electrochemical detectors." Thesis, Loughborough University, 1996. https://dspace.lboro.ac.uk/2134/28323.
Повний текст джерелаАнотація:
Isotope tracer techniques are widely used in biological, agricultural, chemical and medical research. The use of stable isotopes is not complicated by health hazards, dangers of radiation or time limit for experiments as is the case for radioactive isotopes. However, the analytical methods available for the determination of stable isotopes are much less sensitive, considerably more complicated and time consuming than those for radioactive isotopes. Such methods usually require the use of a mass spectrometer and most employ the combustion technique (Dumas method) for sample presentation. Speciation can be achieved by an isotope ratio mass spectrometer coupled to a gas chromatograph (GC) and combustion interface. Such instruments are expensive and labour intensive. Additionally, the consumables and catalysts employed are costly.