Ciencias Exactas y Ciencias de la Salud
Permanent URI for this collectionhttps://hdl.handle.net/11285/551039
Pertenecen a esta colección Tesis y Trabajos de grado de las Maestrías correspondientes a las Escuelas de Ingeniería y Ciencias así como a Medicina y Ciencias de la Salud.
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- Structure analysis through multispectral image processing from a UAV(2017-12-05) Vega Prado, Ernesto; Gordillo Moscoso, José Luis; Hernández Gutierréz, Andrés; Lozáno García, Diego FabíanFor the industry, the inspection of structures has become a tedious task which requires the investment of an important amount of time and resources, yet necessary to guarantee the proper safety measures demanded by laws. With each new improvement in the structural analysis, companies keep trying to find faster and more reliable ways to check their buildings without risking their employees or having to rely on expensive methods of inspection for accurate results. This graduate thesis focuses on the development of a platform for aerial inspection based on multispectral image processing. An unmanned aerial vehicle performs both the navigation and vision processes through an embedded microcomputer and a multispectral sensor that captures images of the structure. The drone is positioned over the target through semiautonomous commands before starting the analysis. Different spectral images of the structure are collected to extract features and use them along with the spectral signatures of the possible failures to classify each flaw on the inspected section. The results of the failure detection are sent to a ground control station where the operator is able to find should there be problems on the structure, hence reducing the time required for the inspection and the amount of resources and workforce required.
- Wavelets for spindle fault diagnosis in high speed machining(2017-12-04) Batallas Moncayo, George Francisco; Morales Menéndez, Rubén; Vallejo Guevara, Antonio; Alcántra Hernández, DianaThe spindle of machining centers must provide high rotational speed, transfer torque and power to the cutting tool during continuous periods of time. The constant forces generate faults in its components where the most important are the shaft and bearings. As the fault increases, it affects other components and may lead to a catastrophic damage and a production stoppage. The maintenance strategies have been evolving in order to prevent irreversible damages. Over the last years, great progress has been made in the condition-based maintenance, particularly in the vibration analysis, where the vibration signature can be associated with the fault. In recent years, several signal-processing techniques have been introduced to extract the features from vibration signals. The WT has caught the attention of the scientific community by its characteristics and its limitless number of wavelets. In this thesis a methodology based on the WT is proposed to detect faults in spindle. The approach is capable of extracting the bearing characteristic frequencies related to the fault from the resonance frequency and the low frequencies information associated with shaft faults. The implemented method contemplates the latest advances in the literature to detect robustly the type of the fault, it is focused on industrial environment were the faults are usually tainted by noise from other machines or by errors in the acquisition. The method is applied to different types of bearing faults to demonstrate its effectiveness and robustness when detecting faults at early stages. In the three studied cases the proposed methodology got several properties; for the CWRU signals the characteristic fault frequency peak got an increase from 6 to 32% compared with the traditional methods; when the signal is tainted by Gaussian noise, the method works more effectively, since in these cases the increase percentage reaches up to 57%. Similarly, in the IMS database the characteristic frequency peak increases from 6 to 70%. Finally, in the machining center database there was not an increment but the method acts as filter which eliminates the undesired frequencies. Experimental results indicate the proposed approach is reliable to detect bearing and shaft faults. It also has a superior diagnosis performance compared to traditional methods in extracting fault features. The method removes most of the noise and can be used in future works as preprocessor.
- Mejoramiento de la producción de Royalactina (MRJP1) en Pichia pastoris, mediante generación de una cepa sobreproductora y su cultivo en biorreactor(2017-12-04) Castañeda Aponte, Héctor Manuel; Rito-Palomares, Marco; Aguilar-Yañes, Jose Manuel; Rodriguez, Mirna AlejandraLa proteína MRJP1 (del inglés Major Royal Jelly Protein 1) mejor conocida como Royalactina (RY) tiene potencial para su explotación en la industria farmacéutica, utilizado como agente hepático-protector, factor estimulante de eritropoyesis, adyuvante para reducir los niveles de colesterol en sangre. En trabajos anteriores se han propuesto diferentes modelos para la expresión de MRJP1, sin embargo, ninguno ha sido idóneo para la producción a escala piloto debido a títulos y rendimientos bajos. El presente trabajo tiene como objetivo aumentar la expresión de la proteína RY en Pichia pastoris, incrementando el número de copias del gen ry, mejorando las condiciones del cultivo en la fase de producción y cultivo en fed-batch en biorreactor. Resultados. Se realizó la construcción de dos diferentes plásmidos para la expresión de RY, uno bajo el control del promotor pAOX1 (inducible con metanol) y un segundo con una versión mejorada del promotor pPPGAP (inducible con glucosa). Los plásmidos se transformaron de forma independiente a una comercial de P. pastoris. Se realizó el fenómeno de hiperresistencia para aumentar el número de copias de RY integradas al genoma de Pichia, al final del proceso se obtuvieron 119 candidatas productoras. Todas las candidatas fueron evaluadas mediante cinéticas realizadas en microplaca. Al final del proceso se obtuvieron 14 cepas sobreproductoras (10 bajo el promotor pAOX1 y 4 con el promotor pPPGAP. Estas cepas productoras se evaluaron en matraces en medio complejo. De las cepas evaluadas se encontró que la cepa G3-5 (portando el promotor pPPGAP) presentaba el mejor rendimiento de producción de RY, cerca de 0.5 g L-1 Posteriormente se llevaron a cabo estudios de mejoramiento de condiciones de cultivo, donde se evaluaron tres medios diferentes y dos temperaturas diferentes para la fase de expresión (25 y 30ºC). Los resultados muestran que se alcanzan rendimientos superiores en medio mineral y 25 ºC con un título final de 1.2 g L -1 . Conclusiones. Se ha generado y caracterizado una cepa de P. pastoris cuyo título y rendimiento son los más altos reportados para la producción recombinante de Royalactina. Dados los parámetros cinticos y de producción de la cepa es una candidata adecuada para futuros trabajos de escalamiento y optimización del bioproceso.