Dissertations / Theses on the topic 'Level liquid measurement'

Bibliography: leaves 93-94.
The coplanar line has been used very successfully as an element in microwave circuits. Small size, high Q-factor, and accurate reproduction, are some of its many advantages. The coplanar transmission lines discussed in this report, are targeted at liquid level measurement, and are typically 30 cm. long. Their operating frequencies are consequently much lower than those of microwave coplanar waveguides, but they have common advantages. The factor which separates the coplanar line from similar liquid level sensors, is that it makes use of the electrical component of the electromagnetic fringe field, setup between its inner conductor, and the surrounding ground plane. The line is effectively a sharply tuned resonator, incorporated as the frequency controlling element of an electronic oscillator. The output frequency falls as a dielectric material penetrates the fringe field. An impressive sensitivity is accomplished by using very thin conductors, thereby ensuring that the fringe field energy is maximised. The most important feature of this sensor is its ability to operate non-intrusively when used with non-conducting vessels, or if employed in a metal tank, the unit can be encased in a dielectric material where the line is non-contacting (the liquid does not penetrate the unit). This combined with its excellent mechanical and electrical stability, and an accuracy better than 1 percent, makes the coplanar line a strong competitor in the field of liquid level measurement. The research began with a theoretical approach, and used lines machined from an Aluminium plate for characteristic impedance measurement. An empirical relation between the gap width, the line thickness, and the characteristic impedance of the line is presented. To assist with the design of the sensor, a lumped capacitance model of the line was developed. Various geometries were tested, and modified until a near linear response to water level was achieved. An advanced engineering model of the level sensor has been developed, which incorporates a stable digital output display, user calibration from the line's end points, and temperature compensation. A T-shaped line, which concentrates the field around its open end, was used for other applications such as, evaporation monitoring, measurement of slurry settlement, and to observe the effect of acids, bases, and salts in water. Various applications of the different coplanar line designs are proposed.

New millimeter wave interferometric, multifunctional sensors have been studied for industrial sensing applications: displacement measurement, liquid-level gauging and velocimetry. Two types of configuration were investigated to implement the sensor: homodyne and double-channel homodyne. Both sensors were integrated on planar structure using MMIC (Microwave Monolithic Integrated Circuit) and MIC (Microwave Integrated Circuit) technology for light, compact, and low-cost design. The displacement measurement results employing homodyne configuration show that sub-millimeter resolution in the order of 0.05 mm is feasible without correcting the non-linear phase response of the quadrature mixer. The double-channel homodyne configuration is proposed to suppress the nonlinearity of the quadrature mixer and to estimate the effect of frequency stability of a microwave signal source without the help of additional test equipment, at the loss of a slight increase of circuit complexity. The digital quadrature mixer is constituted by a quadrature-sampling signal processing technique and takes an important role in the elimination of conventional quadrature mixer's nonlinear phase response. Also, in the same displacement measurement, the radar sensor with the double-channel homodyne configuration provided a better resolution of 0.01mm, the best-reported resolution to date in terms of wavelength in the millimeter wave range, than the sensor employing simple homodyne configuration. Short-term stability of a microwave signal source, which is an important issue in phase sensitive measurement, is also considered through phase noise spectrum obtained by FFT spectral estimator at Intermediate Frequency (IF). The developed sensors demonstrate that displacement sensing with micron resolution and accuracy and high-resolution low-velocity measurement are feasible using millimeter-wave interferometer, which is attractive not only for displacement and velocity measurement, but also for other industrial sensing applications requiring very fine resolution and accuracy.

The aim of the thesis has been to study methods to minimize the slosh when moving liquid-filled packages in packaging machines. An automatic method for generation of the movement of a package in a packaging machine is of growing importance. The main reason is that reduced slosh leads to increased production rate. Progress within measurement technology creates possibilities for new solutions. One purpose has been to find methods and equipment to detect the height of the wave, perhaps at several places or alternatively the entire liquid surface shape. When suitable equipment for detection of the wave movements was found, collected measurements were analyzed and criteria for describing improvements of the slosh properties have been formulated.

Initially a sensor specification was written in order to simplify the search for suitable equipment. Sources of information have mainly been catalogues and Internet. The search resulted in that a number of sensors were borrowed for tests. The results of the tests supported the choice of the most suitable sensor, in this case a laser sensor. The main reason is that the sensors detection ability is good compared to its price. An analysis of the sensors most important properties confirmed the choice of the laser sensor. To be able to compare waves, criteria for what is considered to be good wave properties have been formulated and evaluated.

The work has confirmed that it is difficult to find a simple and cheap solution for wave detection given that the solution should have good detection ability. It has also been difficult to formulate simple but working criteria for wave performance, and this has led to a compromise between the complexity of the criterion functions and the result of the wave score. Ideas about how an automatic method, based on the chosen sensor and the criterion functions, can be implemented, have been introduced. During the work, some interesting discoveries have been made. These have led to better understanding of how some parameters should be chosen, to better understanding of wave movements and to better choice of future work.

Die Dissertation bietet eine umfassende Analyse des quasi-stationären und dynamischen Verhaltens des Bezugspegels in den Nullkammerpegelgefäßen hydrostatischer Füllstandsmesssysteme von Siedewasserreaktoren. Die bislang rein phänomenologisch beschriebenen Übergangsprozesse im Pegelgefäß werden experimentell untersucht und in ihrer Wirkung auf das Messsystem bewertet. Da der Bezugsfüllstand und die Temperaturpulsationen sicherheitsrelevante Messgrößen sind, wird ein Beitrag zur Reaktorsicherheit geleistet. Die neuartigen, nichtinvasiven Verfahren zur Messung der Phasenverteilung im Pegelgefäß liefern realistische, unverfälschte Messdaten. Die Validierung von Simulationscodes und die sicherheitstechnische Bewertung von Siedewasserreaktoren werden dadurch verbessert. Das im CFD-Code Ansys CFX 14 entwickelte und experimentell validierte Modell bietet eine wichtige Grundlage für die numerische Simulation des Füllstandsmesssystems in Ergänzung zu Experimenten und zur Einbindung in Systemsimulationen.

Am 14. Oktober 1999 wurde in Rossendorf die dritte Veranstaltung in einer Serie von Workshops über Meßtechnik für stationäre und transiente Mehrphasenströmungen durchgeführt. Dieses Jahr kann auf auf 11 interessante Vorträge zurückgeblickt werden. Besonders hervorzuheben sind die beiden Hauptvorträge, die von Herrn Professor Hetsroni aus Haifa und Herrn Dr. Sengpiel aus Karlsruhe gehalten wurden. Erneut lag ein wichtiger Schwerpunkt auf Meßverfahren, die räumliche Verteilungen von Phasenanteilen und Geschwindigkeiten sowie die Größe von Partikeln bzw. Blasen der dispersen Phase zugänglich machen. So wurde über einen dreidimensional arbeitenden Röntgentomographen, ein Verfahren zur Messung von Geschwindigkeitsprofilen mit Gittersensoren und eine Methode zur simultanen Messung von Blasengrößen sowie Feldern von Gas- und Flüssigkeitsgeschwindigkeit mit einer optischen Partikelverfolgungstechnik vorgetragen. Daneben wurden interessante Entwicklungen auf dem Gebiet der lokalen Sonden vorgestellt, wie z.B. eine Elektrodiffusionssonde. Neue meßtechnische Ansätze waren ebenfalls vertreten; hervorzuheben ist der Versuch, die Methode der optischen Tomographie für die Untersuchung von Zweiphasenströmungen nutzbar zu machen. Der Tagungsband enthält die folgenden Beiträge: S. John, R. Wilfer, N. Räbiger, Universität Bremen, Messung hydrodynamischer Parameter in Mehrphasenströmungen bei hohen Dispersphasengehalten mit Hilfe der Elektrodiffusionsmeßtechnik E. Krepper, A. Aszodi, Forschungszentrum Rossendorf, Temperatur- und Dampfgehaltsverteilungen bei Sieden in seitlich beheizten Tanks D. Hoppe, Forschungszentrum Rossendorf, Ein akustisches Resonanzverfahren zur Klassifizierung von Füllständen W. Sengpiel, V. Heinzel, M. Simon, Forschungszentrum Karlsruhe, Messungen der Eigenschaften von kontinuierlicher und disperser Phase in Luft-Wasser-Blasenströmungen R. Eschrich, VDI, Die Probestromentnahme zur Bestimmung der dispersen Phase einer Zweiphasenströmung U. Hampel, TU Dresden, Optische Tomographie O. Borchers, C. Busch, G. Eigenberger, Universität Stuttgart, Analyse der Hydrodynamik in Blasenströmungen mit einer Bildverarbeitungsmethode C. Zippe, Forschungszentrum Rossendorf, Beobachtung der Wechselwirkung von Blasen mit Gittersensoren mit einer Hochgeschwindigkeits-Videokamera H.-M. Prasser, Forschungszentrum Rossendorf, Geschwindigkeits- und Durchflußmessung mit Gittersensoren

Am 14. Oktober 1999 wurde in Rossendorf die dritte Veranstaltung in einer Serie von Workshops über Meßtechnik für stationäre und transiente Mehrphasenströmungen durchgeführt. Dieses Jahr kann auf auf 11 interessante Vorträge zurückgeblickt werden. Besonders hervorzuheben sind die beiden Hauptvorträge, die von Herrn Professor Hetsroni aus Haifa und Herrn Dr. Sengpiel aus Karlsruhe gehalten wurden. Erneut lag ein wichtiger Schwerpunkt auf Meßverfahren, die räumliche Verteilungen von Phasenanteilen und Geschwindigkeiten sowie die Größe von Partikeln bzw. Blasen der dispersen Phase zugänglich machen. So wurde über einen dreidimensional arbeitenden Röntgentomographen, ein Verfahren zur Messung von Geschwindigkeitsprofilen mit Gittersensoren und eine Methode zur simultanen Messung von Blasengrößen sowie Feldern von Gas- und Flüssigkeitsgeschwindigkeit mit einer optischen Partikelverfolgungstechnik vorgetragen. Daneben wurden interessante Entwicklungen auf dem Gebiet der lokalen Sonden vorgestellt, wie z.B. eine Elektrodiffusionssonde. Neue meßtechnische Ansätze waren ebenfalls vertreten; hervorzuheben ist der Versuch, die Methode der optischen Tomographie für die Untersuchung von Zweiphasenströmungen nutzbar zu machen. Der Tagungsband enthält die folgenden Beiträge: S. John, R. Wilfer, N. Räbiger, Universität Bremen, Messung hydrodynamischer Parameter in Mehrphasenströmungen bei hohen Dispersphasengehalten mit Hilfe der Elektrodiffusionsmeßtechnik E. Krepper, A. Aszodi, Forschungszentrum Rossendorf, Temperatur- und Dampfgehaltsverteilungen bei Sieden in seitlich beheizten Tanks D. Hoppe, Forschungszentrum Rossendorf, Ein akustisches Resonanzverfahren zur Klassifizierung von Füllständen W. Sengpiel, V. Heinzel, M. Simon, Forschungszentrum Karlsruhe, Messungen der Eigenschaften von kontinuierlicher und disperser Phase in Luft-Wasser-Blasenströmungen R. Eschrich, VDI, Die Probestromentnahme zur Bestimmung der dispersen Phase einer Zweiphasenströmung U. Hampel, TU Dresden, Optische Tomographie O. Borchers, C. Busch, G. Eigenberger, Universität Stuttgart, Analyse der Hydrodynamik in Blasenströmungen mit einer Bildverarbeitungsmethode C. Zippe, Forschungszentrum Rossendorf, Beobachtung der Wechselwirkung von Blasen mit Gittersensoren mit einer Hochgeschwindigkeits-Videokamera H.-M. Prasser, Forschungszentrum Rossendorf, Geschwindigkeits- und Durchflußmessung mit Gittersensoren

The subject of this master‘s thesis is the issue of design of fiber optic sensor for min/max and continuous measurement of liquid level, which could be used for laboratory measurement of optoelectronics. The thesis is divided into the three parts, the first part deals with methods of retrieval level measurement using fiber optic sensors. The second part is made of plant design of optical fiber sensors, it is shown the implementation of measuring devices for liquid level measurement and measured transfer characteristics of the sensors developed. The last part is proposed for laboratory typing tasks using established preparation for teaching in the subject Optoelectronic sensors.

Digoxin is the most commonly used digitalis glycoside for the treatment of congestive heart failure and certain disturbances of cardiac rhythm. The low therapeutic index observed for digoxin and the clinical significance of digoxin therapy have necessitated the development of sensitive analytical methods for the quantitation of digoxin in biological samples. Digoxin may be analysed by several methods including immunoassays, chromatographic procedures and various biological and chemical methods. Immunoassays, both radioimmunoassay (RIA) and fluorescence polarization immunoassay (FPIA) procedures, are used in the clinical laboratory because of their speed, precision, sensitivity and relatively low cost. However, reaction of the digoxin antibodies used in the immunoassay methods with digoxin metabolites, endogenous compounds such as digoxin-like immunoreactive substances (DLIS), and other drugs that may be co-administered with digoxin continues to be a major problem. The lack of specificity of the immunoassay methods for digoxin has led to difficulties in interpretation of assay values. Attempts to compensate for this lack of specificity have included the use of chromatographic systems as elaborate sample handling methods prior to immunoassay. However, since an immunoassay was used for detection of digoxin in these techniques, the specificity may still be quest ionable. A sensitive and specific assay for digoxin using physico-chemical methods for measurement is therefore needed. A method was developed using pre-column derivatization of digoxin and its metabolites with 3,5-dinitrobenzoyl chloride followed by HPLC analysis with electrochemical detection. A maximum sensitivity of 0.883 ng of 3,5-dinitrobenzoyl digoxin (0.394 ng digoxin) was observed using dual electrode detection in the redox mode. Although resolution between derivatized digoxin and its metabolites was obtained, the low yield of the digoxin derivative and the formation of metabolites when small (ng) samples were derivatized made this method unsuitable for evaluating patient samples. A high-performance liquid chromatographic (HPLC) assay using post-column derivatization of digoxin, which separated digoxin from its metabolites and some commonly coadministered drugs, was developed. Post-column (PC) derivatization of digoxin with concentrated hydrochloric acid and dehydroascorbic acid, followed by fluorescence detection, allowed for quantitation within the therapeutic range of digoxin. Steroids which have been reported to cross-react with digoxin antisera were assayed using the HPLC-PC method developed in this study. The steroid samples either did not elute from the HPLC system or did not produce a fluorescent product under these conditions. Serum samples from digitalized patients were evaluated using both the HPLC-PC and the FPIA methods. When compared to the HPLC procedure, the FPIA assay results gave, on average, higher digoxin levels. This may have been due to the inclusion of digoxin metabolites or endogenous compounds with the FPIA assay. Serum samples from undigitalized patient groups where high DLIS levels have been reported were also evaluated. These included umbilical cord blood samples and samples from hypertensive patients, renal failure patients and hepatic failure patients. Comparison of the HPLC-PC and FPIA methods demonstrated that the HPLC-PC assay gave fewer false positive results than the FPIA. The HPLC-PC assay developed for analysis of digoxin was unaffected by the presence of digoxin metabolites, numerous steroids, co-administered drugs and endogenous compounds, most of which have been reported to give false positive results with the FPIA.
Pharmaceutical Sciences, Faculty of
Graduate

碩士
國立臺灣大學
工程科學及海洋工程學研究所
107
This study uses gas as the ultrasonic sound transmission medium. Since the transducers used is pulse-echo, the ultrasonic waves interfere with each other when they are transmitted. So that when the signal is received, the wave packets will overlap each other, causing misjudgment. It is difficult to clearly receive echoes without an echo amplifier circuit. Therefore, multiple acrylic tubes are used as shields to guide the self-receiving transducers to measure the liquid level. At the same time, the change of the mechanism is utilized to amplify the echo energy so that the echo signal can be received. When the liquid level is stationary, the current liquid level position can be reversed by measuring the inclination angle of the liquid surface by the acrylic tube mechanism. If the liquid level is under linear shaking, the average liquid level can be calculated through the sloshing process of the liquid surface. The longitude can reach ±0.5cm or less, and the measurement result can be more accurate and stable at low cost. Operates with a wider range of applications.

碩士
逢甲大學
產業研發碩士班
97
This paper presents a wireless capacitance-inductance coupling microsensor for liquid-level measurement. The microsensor consists of a parallel-plate capacitor, a planar coil inductor and a polyimide thin film. An inductor-capacitor (LC) resonant circuit is provided for measuring liquid-level by analyzing the shift of resonance frequency. The development of sensors is following the procedures of simulation, design, fabrication, and test. The MEMS (Microelectromechanical System) fabrication technology is used to minimize device dimension and to increase production efficiency. Based on passive wireless transmission and sensing circuit design, the microsensor can be constantly measuring without supplying electrical power source. The wireless signal measurement system includes an arbitrary function generator, a spectrum analyzer, an RF power amplifer and signal processing circuits. The typical sensor dimension is 8mm×8mm×0.77mm that contains a 61-turns nickel-electroplated micro-coil inductor and a capacitor with an area of 5000μm×5000μm.

碩士
國立成功大學
奈米科技暨微系統工程研究所
97
In this study, the optical fiber liquid level sensor based on fiber Bragg grating and the optical fiber pressure sensor based on Faby-Perot interferometer have been designed and fabricated. The liquid level sensor makes use of the fiber Bragg grating that glued onto the centric surface of uniform strength cantilever beam. The liquid level sensor can measure the range from 0.45m to 0.78m with the sensitivity of 0.01491nm/cm and it exhibits an approximately linear response. The design and fabrication of the pressure sensor based on Fabry-Perot interferometer utilize the MEMS technique and only needs a few of simple procedures. The pressure sensing membrane consists of a base polyimide layer, a metal reflective layer, and a SU-8 layer covered on the metal layer. The measurement range of the pressure sensor is from 0.98kPa to 6.86kPa with the sensitivity of 0.1569μm/kPa. The simultaneous measurement systems of liquid level and specific gravity have also developed in this study. Any two sensor elements in this thesis can be combined to a simultaneous measurement system of liquid level and specific gravity. The system can reduce the error to minimum by way of calibration of the sensor elements. The average errors of these systems for specific gravity are 0.0153, 0.0247 and 0.0357, respectively. And the average errors of these systems for liquid level are 0.0120m, 0.0144m and 0.0273m, respectively.

Die Dissertation bietet eine umfassende Analyse des quasi-stationären und dynamischen Verhaltens des Bezugspegels in den Nullkammerpegelgefäßen hydrostatischer Füllstandsmesssysteme von Siedewasserreaktoren. Die bislang rein phänomenologisch beschriebenen Übergangsprozesse im Pegelgefäß werden experimentell untersucht und in ihrer Wirkung auf das Messsystem bewertet. Da der Bezugsfüllstand und die Temperaturpulsationen sicherheitsrelevante Messgrößen sind, wird ein Beitrag zur Reaktorsicherheit geleistet. Die neuartigen, nichtinvasiven Verfahren zur Messung der Phasenverteilung im Pegelgefäß liefern realistische, unverfälschte Messdaten. Die Validierung von Simulationscodes und die sicherheitstechnische Bewertung von Siedewasserreaktoren werden dadurch verbessert. Das im CFD-Code Ansys CFX 14 entwickelte und experimentell validierte Modell bietet eine wichtige Grundlage für die numerische Simulation des Füllstandsmesssystems in Ergänzung zu Experimenten und zur Einbindung in Systemsimulationen.

Dupla diplomação dom a UTFPR - Universidade Tecnológica Federal do Paraná
Automation of industrial activities aim to improve the efficiency of the productive processes while reducing costs and increasing safety. In industrial laundries, the detergent level measurement is a key element for asset management, mainly due to the necessity of maintaining a continuous flow of washing processes. Therefore, this work presents a solution implemented in the industrial laundry reservoirs of Santa Casa da Misericórdia de Bragança, in Portugal, using an Internet of Things (IoT) approach, which integrates a Wi-Fi based measurement system, capable of monitoring and recording the detergent liquid level from reservoirs in real-time. Thereby, a microcontrolled system was developed to perform level measurements using an ultrasonic sensor, in which data is sent to a database and, through a web based platform, the client can remotely access the measurement results. In order to facilitate the physical installation of the developed hardware in the existent setup, a custom-made enclosure was designed and 3D printed.
A automação das atividades industriais tem como objetivo melhorar a eficiência de processos produtivos, reduzindo custos e aumentando a segurança. Em lavanderias industriais, a medição de nível de detergente líquido é um elemento fundamental para o gerenciamento de ativos, principalmente devido à necessidade de manter um fluxo contínuo dos processos de lavagem. Dessa forma, o trabalho apresenta uma solução implementada nos reservatórios da lavanderia industrial da Santa Casa da Misericórdia de Bragança, em Portugal, usando uma abordagem de internet das coisas, na qual integra um sistema de medição com conexão Wi-Fi, capaz de monitorar e registrar o nível de detergente líquido dos reservatórios em tempo real. Com isso, foi desenvolvido um sistema microcontrolado responsável por realizar as medições de nível ulilizando sensor ultrasônico, na qual os dados são enviados para um banco de dados e, através de uma plataforma web, o cliente consiga acessar de forma remota o resultado das medições. Para facilitar a instalação do sistema nos reservatórios, um bujão foi desenhado sob medida e impresso em 3D.