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Object manipulation by collaborative autonomous underwater vehicles driven by a model-free second-order sliding mode controller with finite-time convergence

JOSUE GONZALEZ GARCIA (2023, [Artículo])

https://orcid.org/0000-0001-5657-380X

The use of Autonomous Underwater Vehicles (AUV) has expanded in recent years to include them in inspection, maintenance, and repair missions. These missions require the automation of tasks such as autonomous navigation and station-keeping, which are pretty challenging due to the complexity of the vehicle itself and the underwater environment. Traditional control strategies have been used to deal with those problems before, but their performance is limited since they do not consider non-linearities, external disturbances, or model uncertainties. Non-traditional controllers have been explored too, but have shortcomings such as being model-based, parameter-dependant, or so. Additionally, the nature of some objects implies the involvement of multiple vehicles to manipulate them, making the manipulation mission even harder. Collaboration of AUVs is a strong challenge since underwater communications are limited or null. An advanced control strategy dealing with the trajectory tracking and the station-keeping problem would be desirable for simplicity and robustness. If this controller could also help coordinate multiple vehicles without requiring them to communicate with each other, it would make collaborative manipulation tasks reachable. For this purpose, a model-free high-order Sliding Mode Controller (SMC) is presented in this project. Unlike other control approaches, the proposed control strategy achieves finite-time convergence to a practical zero error in a time-base that the user can arbitrarily define. This characteristic will be used to coordinate the navigation of two AUVs to manipulate an object underwater. The performance of the proposed controller was evaluated by numerical simulations and experiments in a semi-Olympic swimming pool and compared with classic and state-of-the-art control strategies regarding trajectory tracking and station-keeping problems. Results have shown that the proposed controller can achieve finite-time convergence of the tracking errors to a practical zero value in the predefined time-base. Results also demonstrated that the convergence time could be arbitrarily selected by the user and achieved by the controller resulting in, as far as the author knows, the first controller with this characteristic for AUVs navigation. The simulations and experiments also showed that the proposed controller outperformed classical and state-of-the-art controllers regarding the Root Mean Square of the tracking errors and energy consumption. Finally, the proposed model-free high-order SMC coordinated two BlueROV2 vehicles in a collaborative manipulation mission without vehicle-to-vehicle communication. Numerical simulation results confirmed that the proposed controller could manage the vehicles to follow a predefined coordinated trajectory to approach, grip, transport, and release an object without communicating with each other.

Doctor of Philosophy In Engineering Science

INGENIERÍA Y TECNOLOGÍA CIENCIAS TECNOLÓGICAS TECNOLOGÍA DE LA INSTRUMENTACIÓN INGENIERÍA DE CONTROL INGENIERÍA Y TECNOLOGÍA CIENCIAS TECNOLÓGICAS TECNOLOGÍA NAVAL VEHÍCULOS SUBMARINOS

Gestión de proyectos de TIC en Sinersystech con metodología de desarrollo DevOps

Juan Carlos Espino Ortega (2023, [Otro, Trabajo de grado, maestría])

La gestión de proyectos de TIC suele volverse caótica cuando no existe una metodología, con la suficiente madurez, de desarrollo, seguimiento y tampoco las herramientas necesarias para dar seguimiento a las actividades que se realizan en todas las etapas del proyecto. En este artículo abordaremos el uso de la metodología DevOps, así como las aplicaciones de software que pueden soportar el uso de esta para dar seguimiento al desarrollo de los proyectos de TIC en Sinersystech, se realiza revisión de estado del arte, se desarrolla cuestionario con un enfoque cualitativo para entender la situación actual de la empresa y para concluir se documentan las herramientas que nos pueden apoyar en los procesos de desarrollo de software dentro de la empresa adoptando la metodología de desarrollo DevOps, los beneficios de la integración de esta en todas las etapas del desarrollo optimizando, costos, tiempos de entrega y resultado hacia los clientes.

Gestión de proyectos Metodología de gestión de proyectos DevOps INGENIERÍA Y TECNOLOGÍA CIENCIAS TECNOLÓGICAS TECNOLOGÍA DE LAS TELECOMUNICACIONES TECNOLOGÍA DE LAS TELECOMUNICACIONES

A Comparison of Multi-Label Text Classification Models in Research Articles Labeled With Sustainable Development Goals

Roberto Carlos Morales-Hernández Joaquín Gutiérrez Jaguey David Becerra-Alonso (2022, [Artículo])

"The classification of scientific articles aligned to Sustainable Development Goals is crucial for research institutions and universities when assessing their influence in these areas. Machine learning enables the implementation of massive text data classification tasks. The objective of this study is to apply Natural Language Processing techniques to articles from peer-reviewed journals to facilitate their classification according to the 17 Sustainable Development Goals of the 2030 Agenda. This article compares the performance of multi-label text classification models based on a proposed framework with datasets of different characteristics. The results show that the combination of Label Powerset (a transformation method) with Support Vector Machine (a classification algorithm) can achieve an accuracy of up to 87% for an imbalanced dataset, 83% for a dataset with the same number of instances per label, and even 91% for a multiclass dataset."

Classification algorithm, multi-label text classification, problem transformation method, scientific articles, sustainable development goals, text classification INGENIERÍA Y TECNOLOGÍA CIENCIAS TECNOLÓGICAS TECNOLOGÍA DE LOS ORDENADORES LENGUAJES ALGORÍTMICOS LENGUAJES ALGORÍTMICOS

Efecto de la deformación y contenido Mg en las Propiedades Mecánicas de la Aleación Al2.33CuXMg

Enrique Burciaga Castillo (2022, [Tesis de maestría])

El sistema Al-Cu-Mg es uno de los sistemas más estudiados debido a la importancia

tecnológica de las aleaciones base aluminio a nivel mundial. Sin embargo, la mayoría de

los estudios no abordan el efecto sinérgico de la adición de algún elemento aleante

(magnesio) con la deformación plástica, sino que se enfocan en determinar los efectos

aislados de cada variable. Así la presente investigación, se enfoca en evaluar la

contribución conjunta de los efectos mencionados principalmente sobre los mecanismos

de endurecimiento y la propiedad mecánica de dureza a fin de contribuir a un mayor

entendimiento de esta interacción.

En el presente trabajo de investigación se estudió la aleación Al2.33Cu en función de su

deformación (ξ), reduciendo el espesor a 30% y 50%, estudiando sus propiedades

mecánicas bajo la adición de Mg en sus diferentes etapas de tratamiento térmico y

mecánico.

Se fabricaron aleaciones mediante el proceso de fundición, utilizando diferentes

cantidades de Mg (0, 1.78, 1.96 y 2.24%) en la aleación de aluminio Al2.33Cu, se

extruyeron las muestras, seguido se realizó un tratamiento de solución a 495°C con

temple en agua y posteriormente se realizó una curva de envejecido (1, 2, 4.5, 10, 20,

45, 100, 200, 450, 1000, 2000, 4500 y 10000 min) a una temperatura de 195°C.

Se realizó caracterización por microscopía óptica, difracción de rayos X y Microscopía

electrónica de barrido en sus primeras etapas (colada, extrusión y solución), así como

mediciones de micro dureza en cada una de sus etapas.

Esta investigación se enfocó en la importancia y el efecto del magnesio en las aleaciones

de AlCu y el efecto de la deformación, como consecuencia en el impacto las propiedades

mecánicas de dureza de la aleación.

Mg INGENIERÍA Y TECNOLOGÍA CIENCIAS TECNOLÓGICAS TECNOLOGÍA METALÚRGICA PRODUCTOS METALÚRGICOS (ESPECIALES) PRODUCTOS METALÚRGICOS (ESPECIALES)

4d printing research trends and applications in the medical field: a scientometric analysis

MARISELA RODRIGUEZ SALVADOR (2022, [Tesis de maestría])

https://orcid.org/0000-0002-5206-3447

Innovation plays a key role on a company’s either success or failure. But innovation is not just the creating or adopting new technologies; it is also directly connected with a solid strategic planning. Competitive technology intelligence is based on the systematic and ethical process of gathering, analyzing and transforming information into actionable knowledge. It aims to support decision making and strategic planning, because the knowledge produced by this methodology constitutes an early warning for research, development and innovation [19]. Three-dimensional (3D) printing is a technique of additive manufacturing that has revolutionized engineering, product design and manufacturing, as it allows the rapid conversion of digital 3D model information into physical static objects [45]. However, in the last few years a new possibility has been introduced to add ’time’ as a new dimension to create 4D printing. The medical field keeps changing and progressing at a high speed with new technologies emerging every day. 4D printing on the medical field is an area where it is necessary to provide decision makers with an overview of technological knowledge that helps them generate innovation opportunities. On this thesis, a Competitive technology intelligence approach was executed to identify trends in 4D printing technologies applied to the medical field, in order to provide relevant information through a technological landscape to support decision makers to uncover innovation opportunities. The results of the analysis revealed that most of the research developed is on the materials category, which relates completely to the fact that smart materials are the key difference between 3D and 4D printing. Most of the researches focus on shape memory polymers, hydrogels and liquid crystal elastomers. On the processes category researched is focused on the physical configuration of the printing model, printing parameters and adapting machines to modify the printing configurations. As for the applications, three main subcategories were identified, hollow tubes/stents, tissue engineering and drug delivery. According to the growth kinetics it is a field that although is fairly new, keeps growing and will keep gaining attention.

Maestra en Ciencias con Especialidad en Sistemas de Manufactura

INGENIERÍA Y TECNOLOGÍA CIENCIAS TECNOLÓGICAS TECNOLOGÍA MÉDICA OTRAS

Las nuevas redes de centros de desarrollo tecnológico aplicado. Una aproximación al caso británico

Germán Herrera Bartis Patricia Gutti (2023, [Artículo, Artículo])

Este trabajo lleva a cabo un análisis de la experiencia de Catapult, un programa guberna­mental del Reino Unido surgido una década atrás consistente en la creación y sosteni­miento de una red de nuevos centros de desarrollo tecnológico aplicado destinados a atender las demandas y requerimientos de los actores productivos privados de dicho país. A través del análisis de numerosos documentos oficiales, auditorías del programa y entre­vistas a actores clave el artículo analiza las características centrales de la política en cues­tión, incluyendo los elementos que definen la gobernanza del sistema, el esquema de fi­nanciamiento vigente, el alcance de las actividades tecnológicas de los centros y su vínculo con las empresas privadas.

Tecnología Innovación Desarrollo tecnológico Política industrial Reino Unido CIENCIAS SOCIALES CIENCIAS SOCIALES

Low thermal conductivity solar domestic water heater

MIGUEL ANGEL PORTA GANDARA JOSE LUIS FERNANDEZ ZAYAS JUAN FRANCISCO VILLA MEDINA NORBERTO CHARGOY DEL VALLE (2022, [Artículo])

"Solar domestic water heaters (SWH) with thermosyphon circulation are the most common commercial applications of solar energy in Mexico. They are also becoming popular in the rest of the world, given their simplicity, good economic returns, and sustainability. Traditionally the solar collector, the piping, and the storage tank are built of copper and steel. However, wáter quality in many parts of the Mexican Northwest has high mineral contents and, when heated, results in early metal pitting corrosion of SWH parts. Short-lived water heaters are bad promoters of the technology. In this work, a SWH thermoplastic Chlorinated Polyvinyl Chloride (CPVC) is built and tested under real operating conditions in La Paz, BCS, Mexico. The optimal design is detected with the aid of a suitable numerical model. Results reveal that a full SWH-CPVC can be technically and economically convenient for the weather conditions of the Northwestern states of Mexico."

Low thermal conductivity solar water heater CPVC solar water heater Solar water heater cooper pitting corrosion Thermosiphon circulation INGENIERÍA Y TECNOLOGÍA CIENCIAS TECNOLÓGICAS TECNOLOGÍA ELECTRÓNICA DISPOSITIVOS TERMOELÉCTRICOS DISPOSITIVOS TERMOELÉCTRICOS

EFFICIENT FLUORESCENT AND PHOSPHORESCENT OLEDs BY SPIN COATING TECHNIQUE AND A NEW ANODE BASED ON CONDUCTIVE PEDOT:PSS

Luis Abraham Lozano Hernández (2020, [Tesis de doctorado])

"Fluorescent and phosphorescent Organic Light Emitting Diode (OLED) devices were fabricated by solution process and optimized. From their basic characterization (J-V-L curves, electroluminescence spectra) external quantum efficiency (EQE) was calculated. Two small molecule, carbazole derivatives (CZ-1 and CZ-2), previously reported and used for OLEDs showed very good luminances (~ 4000 cd/m2) and current densities (< 200 mA/cm2) resulting in a high EQE (9.5 %). Likewise, fluorescent OLEDs based in the new polymer PF-2F presented an acceptable performance even on a simple architecture with a good EQE (2.6 %), photoluminescence quantum yield (PLQY) about 1 and excellent properties of processability. The influence of its CF3 group in the optical, chemical, electronic and mechanical properties in OLEDs was determined.

Also, a new family of three fluorescent oligomers (BT-F32, BT-F42 and BT-F52) with excellent properties in solution, high PLQY (~1) and highly luminescent, were used in simple and multilayer OLEDs achieving a very high luminance (29 499 cd/m2). These oligomers have different chain lengths, which influence the device luminance, efficiency and their lifetime. Lifetime was monitored and the stretched exponential decay (SED) model was used in order to obtain the device half-life (LT50). Also, phosphorescent devices, based on a host/guest system (PVK:Ir(ppy)3), were prepared, the influence of the electron transport layer (ETL) into the electron/hole ratio was analyzed.

By using a new proposed method, a PEDOT:PSS anode was developed and applied in rigid and flexible substrates, with low sheet resistance (40 Ω/□) and acceptable transmittance (> 85%). This new proposed method consists in volume evaporation, in which basically the loss of water induces closeness among the conductive fractions of PEDOT. This PEDOT:PSS anode easy of fabricating following an economical procedure could be applied not just in OLEDs but in other optoelectronic devices such as organic photovoltaic cells (OPVs), perovskite solar cells (PeSCs), etc."

OLEDs Fluorescence Phosphorescence PEDOT:PSS Polymer Anode INGENIERÍA Y TECNOLOGÍA CIENCIAS TECNOLÓGICAS TECNOLOGÍA ELECTRÓNICA DISPOSITIVOS SEMICONDUCTORES DISPOSITIVOS SEMICONDUCTORES