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Preparation And Characterization Of Cigss Solar Cells And Pv Module Data AnalysisShirolikar, Jyoti 01 January 2005 (has links)
In this thesis, multiple activities have been carried out in order to improve the process of CIGSS solar cell fabrication on a 4" x 4" substrate. The process of CIGSS solar cell fabrication at FSEC's PV Materials Lab involves a series of steps that were all carried out manually in the past. A LABVIEW program has been written to carry out automated sputter deposition of Mo back contact, CuGa, In metallic precursors on a soda lime glass substrate using a stepper motor control for better uniformity. Further, selenization/ sulfurization of these precursors was carried out using rapid thermal processing (RTP). CIGS films were sulfurized using chemical bath deposition (CBD). ZnO:Al was deposited on the CIGSS films using RF sputtering. A separate LABVIEW program was written to automate the process of ZnO:Al deposition. Ni/Al contact fingers were deposited on the ZnO:Al layer using the e-beam evaporation technique. Further, in order to test these solar cells in-house, a simple current-voltage (IV) tracer was fabricated using LABVIEW. A quantum efficiency (QE) measurement setup was built with guidance from the National Renewable Energy Laboratory (NREL). Lastly, analysis of data from photovoltaic (PV) modules installed on the FSEC test site has been carried out using a LABVIEW program in order to find out their rate of degradation as time progresses. A 'C' program has also been written as an aid for keeping a daily log of errors in data and for troubleshooting of the same.
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Diesel Engine Experimental Design and Advanced Analysis TechniquesDavis, Jonathan Michael 20 October 2011 (has links)
No description available.
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Diseño e implementación de un sistema de automatización de ensayos característicos de máquinas eléctricas asíncronas: diseño e implementación de un instrumento virtual para el análisis de los resultados de los ensayos característicos de un motor asíncrono trifásico en entorno LabVIEWRodríguez Reátegui, Julio Diego 20 May 2013 (has links)
En la actualidad, la utilización de los instrumentos virtuales ha venido incrementándose en
aplicaciones enfocadas a las ciencias e ingeniería. Esto se debe a que, a diferencia de los
instrumentos tradicionales de laboratorio, estas son herramientas basadas en software,
las cuales utilizan el hardware de una computadora o estación de trabajo para realizar las
tareas para las cuales han sido diseñadas, lo cual le da grandes ventajas como una
mayor portabilidad, personalización, adaptabilidad e interconectividad con otros sistemas.
El objetivo de la tesis es la utilización de un entorno de desarrollo creado por la empresa
National Instruments, llamado LabVIEW. En dicho entorno, se diseñará e implementará un
instrumento virtual, cuyo propósito es el de ser usado para el análisis de los resultados
obtenidos en el proceso de ejecución de los ensayos característicos realizados a un motor
asíncrono trifásico. Para ello, el instrumento virtual deberá ser capaz de establecer una
comunicación con un hardware externo encargado de llevar a cabo dichos ensayos de
forma automática. Dicha comunicación enlazará al instrumento virtual con una tarjeta de
adquisición de datos, lo cual permitirá al usuario del instrumento, ingresar datos de placa
y parámetros de ensayo pertinentes, para que estos sean enviados al resto del sistema
para la correcta realización de los ensayos. Así mismo, el instrumento virtual debe ser
capaz de usar esta comunicación para recibir valores correspondientes a los resultados
de los ensayos realizados en dicha máquina eléctrica, provenientes de la tarjeta de
adquisición de datos mencionada.
Utilizando los valores obtenidos durante el desarrollo de los ensayos, el instrumento
realizará cálculos matemáticos pre-programados con la finalidad de poder mostrar en
pantalla los parámetros del circuito eléctrico equivalente y las gráficas características
correspondientes para el análisis del motor asíncrono trifásico ensayado con el fin de
describir, de forma gráfica, su comportamiento y eficiencia.
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Investigating the influence of fabrication parameters on the diameter and mechanical properties of polysulfone ultrafiltration hollow-fibre membranesRugbani, Ali 12 1900 (has links)
Thesis (MScEng (Mechanical and Mechatronic Engineering))--University of Stellenbosch, 2009. / ENGLISH ABSTRACT: Polysulfone hollow-fibre membranes were fabricated via the dry-wet solution
spinning technique. The objective was to demonstrate the influence of the various
fabrication parameters on the diameter and mechanical properties of the hollow-fibre
membranes and to optimize the spinning process by controlling these parameters with
a computer control system. The effects of the operation parameters were investigated
using an experimental design based on a fractional factorial method (Taguchi’s design
of experiments). The parameters that were considered are the spinneret size, dope
solution temperature, bore fluid temperature, coagulation bath temperature, dope
extrusion rate, bore flow rate and the take-up speed. A new pilot solution spinning
plant was installed and upgraded, and a computer control system, based on LabView,
was developed to control, monitor and log the experimental data. The diameter of the
hollow-fibres were determined using a scanning electron microscope (SEM) while the
mechanical properties were measured using a tensile tester. The effects of diameter
size and wall thickness of the hollow-fibres on the performance of the membranes
were studied.
The results showed the significance of the fabrication parameters that dominate the
diameter and strength of the hollow-fibres. / AFRIKAANSE OPSOMMING: Polisulfoon holvesel membrane is met ‘n droë-nat oplossingspin proses vervaardig.
Die doel hiermee was om die invloed van verskeie vervaardigingsparameters op die
deursnee en meganiese eienskappe van die holvesel membrane te demonstreer asook
om die spin proses te optimeer deur gerekenariseerde beheer van die aanleg. ‘n
Eksperimentele ontwerp, gebaseer op ‘n gedeeltelike faktoriaal metode (Taguchi se
eksperimentele ontwerp) is gebruik om die invloed van die vervaardigingsparameters
te ondersoek. Die parameters wat oorweeg is, is spindop grootte, materiaal
temperatuur, boorvloeistof temperatuur, stolbad temperatuur, materiaal ekstrusie
tempo and opwen spoed. ‘n Nuwe oplossingspin loodsaanleg was geïnstalleer en
opgegradeer en ‘n rekenaar beheerstelsel, gebaseer op LabView, is ontwikkel om die
aanleg te beheer, moniteer en eksperimentele data te stoor. Die deursnee van die
holvesel is gemeet met ‘n skanderingelektron mikroskoop (SEM) terwyl die
meganiese eienskappe bepaal is met ‘n trektoets apparaat. Die effek van die deursnee
en wanddikte van die holvesels op die werkverrigting van die membrane is ook
bestudeer.
Die resultate toon watter vervaardigingsparameters is beduidend vir die deursnee en
sterkte van die holvesels.
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The Design and Development of a Perceptual-Based Haptic Display DeviceAkhter, Sohaib 07 August 2013 (has links)
Graphical information presented as pictures, graphs, maps, and the like are an important media for relaying knowledge and are a fundamental means of education rarely experienced by people who are blind or have a severe visual impairment. This thesis presents the design, development and testing of a multiple finger, haptic matrix dynamic display device capable of relaying graphical information through simulated textures. The design is based on user perception studies that determined which hand constraints provided the best tradeoff between simplicity of design, accuracy and time to answer. The best design was one that incorporated multiple fingers in close proximity to each other and restricted wrist rotation. Upon further testing after the development of the device, evidence was gathered to show its effectiveness. Although subjects could determine key information from the simulated textures, there is a clear mismatch between the simulated representations of the objects and their tactile or embossed counterparts. There is some evidence that shows that the spatial resolution of the actuators may be a source of this error and also some evidence to state that it is the inability to track the edges that causes the difference between determining the physical diagrams and the simulated. On the other hand, results on determining locations using simulated maps were far closer to the control texture maps used than the results for object diagrams. Further studies could be done to determine the effect of higher actuator spatial resolution on object identification and edge tracking.
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Upgrade of a LabVIEW based data acquisition system for wind tunnel test of a 1/10 scale OH-6A helicopter fuselageLines, Philipp A. 06 1900 (has links)
Approved for public release, distribution is unlimited / For over half a century the NPS Aerolabʼ Low Speed Wind Tunnel located in Halligan Hall of the Naval Postgraduate school has served to provide students and faculty with meaningful aerodynamic data for research and problem analysis. New data acquisition hardware was installed three years ago but never fully verified, and contained no integrated software program to collect data from the strain-gauge balance pedestal. Existing National Instruments based hardware for the NPS low-speed wind tunnel was reconfigured to obtain data from the strain-gauge pedestal. Additionally, a data acquisition software program was written in LabVIEWâ to accommodate the hardware. The Virtual Instruments (VI) program collects and plots accurate data from all four strain gauges in real-time, producing non-dimensional force and moment coefficients. A research study on the performance of an OH-6A helicopter fuselage was conducted. NPS Aerolabʼ wind tunnel tests consisted of drag, lift, and pitching moment measurements of the OH-6A along yaw and angle-of-attack sweeps. The results of the NPS wind tunnel data were compared against testing conducted on a full-scale OH-6A helicopter in NASA Ames' 40 ft. x 80ft. wind tunnel, along with the U.S. Army's Light Observation Helicopter (LOH) wind tunnel tests. Results of current testing substantiate the LabVIEWâ code. / Ensign, United States Navy
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Automated hand-forearm ergometer data acquisition and analysis systemGude, Dana Maxine January 1900 (has links)
Master of Science / Department of Electrical & Computer Engineering / Steve Warren / Handgrip contractions are a standard exercise modality to evaluate muscular system performance. Most conventional ergometer systems that collect handgrip contraction data are manually controlled, placing a burden on the researcher to guide subject activity while recording the resultant data. Further, post-processing tools for this type of experiment are not standardized within the domain, which requires investigators to process their data with multiple tool sets and often create custom tool sets for that purpose. This can make experimental data difficult to compare and correlate, even within the same research group.
This thesis presents updates to a hand-forearm ergometer system that automate the control and data-acquisition processes as well as provide a tool set to post process hand contraction data. The automated system utilizes a LabVIEW virtual instrument as the system centerpiece; it provides the subject/researcher interfaces and coordinates data acquisition from both traditional and new sensors. The tool set also incorporates a collection of MATLAB scripts that allow the investigator to post process these data in a standard way, such as automating the processes of noise floor removal, burst start/stop time identification, and mean/median frequency calculation in electromyograms (EMGs).
The tool set has proven to be a viable support resource for experimental studies performed by the Kansas State University Human Exercise Physiology lab that target muscle fatigue in human forearms. Initial data acquired during these tests indicate the viability of the system to acquire consistent and physiologically meaningful data while providing a usable tool set for follow-on data analyses.
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A cooler Penning trap to cool highly charged radioactive ions and mass measurement of 24AlChowdhury, Usman 30 June 2016 (has links)
Penning trap mass spectrometry (PTMS) can be used to test the Standard Model (SM) and to answer the questions related to the origin and abundance of the elements in the universe. There are several facilities worldwide specialized in PTMS and some of them can measure the masses of isotopes with half-lives in the range of milliseconds. TRIUMF’s ion trap for atomic and nuclear science (TITAN) is one such facility. In mass measurement the precision is linearly proportional to the charge state of the ion of interest. To increase the charge state, ions are charge-bred using an electron beam ion trap (EBIT) at TITAN. However, the charge breeding process introduces an energy spread among the ions which adversely affects the precision of the mass measurement. To overcome this problem a cooler Penning trap (CPET) was designed, assembled and is now being tested off-line. This thesis presents the first systematic test results of CPET. We also present the result of the first Penning trap mass measurement of the isotope 24Al, which is five times more precise than the previous atomic mass evaluation (AME2012) value. The precise and accurate mass of 24Al is important for both astrophysics and for test of the standard model (SM). The resonance energy (E_r) calculated for the 23Mg(p,gamma)24Al reaction using the ground state mass of 24Al reported in this thesis shows a 2s deviation from the direct measurement. On the other hand, tests of the SM by evaluating f_t values using isospin T = 1 nuclides have reached a high precision level. Effort is now shifting towards the T = 2 nuclides, which are far from stability compared to their T = 1 counterparts. For this reason, the ground state masses of T = 2 nuclides and of their decay products are required to be known with high precision. 24Al is the daughter of one such nucleus, 24Si. The ground state mass of 24Al reported in this thesis will be useful to test the SM. / October 2016
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Metody analýzy vibračních signálů / Methods of analysis of vibration signalsSivera, David January 2017 (has links)
The aim of the thesis is to focus on the different methods of analysis of vibration signals. Focusing on the physical fundamentals of vibrations and a description of their origin in an electrical machine. Describe the vibration sources from mechanical across the electromagnetic to the aerodynamic. Defining the current defects of electric machines and sensors suitable for the measurement of vibrations in an electric machines. Introduction to the methods of analysis of vibration signals in the time and frequency domain. Then using some of these methods for the analysis of vibration signals measured asynchronous motors with different manufacturer defined production defect. The conclusion is composed from the comparison between measured and analyzed results.
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Investigation of DC Motors for Electric and Hybrid Electric Motor Vehicle Applications Using an Infinitely Variable TransmissionGroen, Benjamin Carson 13 January 2011 (has links)
Since the early 1900's demand for fuel efficient vehicles has motivated the development of electric and hybrid electric vehicles. Unfortunately, some components used in these vehicles are expensive and complex. AC motors, complex electronic controllers and complex battery management systems are currently used in electric (EV) and hybrid vehicles. This research examines various motors and speed control methods in an attempt to help designers identify which motors would be best suited for an EV powertrain application. The feasibility of using DC motors coupled with an Infinitely Variable Transmission (IVT), to obtain an innovative new electric or hybrid electric powertrain is also presented. The results of this research include an extensive review of the many motor types including a comparison chart and motor hierarchy. An experiment was designed and built to test motorspeed control methods. Testing with two DC separately-excited motors and a differential as an IVT was also conducted. These tests revealed that field weakening appears to be a viable low-costspeed-control method. Testing of these motors, coupled with an IVT revealed that the output of a differential or planetary gear set can be controlled by varying the speed of the inputs. Combining this information in a product development mentality led to the concept of using one DC motor as a power or traction motor while another motor acts as a speed controller, with the method of speedcontrol on the speed control motor being field weakening. This concept allows most of the power to be delivered at an efficient rate with a simple form of speed control. This concept may also eliminate the need for expensive, complex electronic motor controllers. This approach could be used to improve the safety and reduce battery management requirements by lowering the operating voltage of the entire system.
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