bluuebunny/crossref_metadata_2025 huggingface dataset:
Dietary Diversity among Children Aged 6-23 Months in Bangladesh: Determinants and Inequalities
Authors: Khanam Moriam , Sarker Abdur Razzaque
Published: August 2023

Inadequate dietary intake is one of the causes of childhood undernutrition and associated morbidity and mortality in many low and middle-income countries, including Bangladesh. The study aims to identify the prevalence, associated factors, and socio-economic inequalities in minimum dietary diversity, minimum meal frequency, and minimum acceptable diet among 6-23 month-children in Bangladesh. This study uses data from the latest round of the Bangladesh Demographic and Health Survey (BDHS) 2017-18. Descriptive analyses have been conducted to report frequencies and percentages of the socio-demographic and economic characteristics of 6-23 months aged children. Bivariate and multiple logistic models are used to identify the predictors of each dietary indicator. In addition, we estimate concentration indices and use Wagstaff-based decomposition analysis to identify socio-economic inequalities in dietary diversity and their contributing factors. The study finds the prevalence of minimum dietary diversity, minimum meal frequency, and minimum acceptable diet as 38%, 81%, and 36%, respectively. Education of mothers is a significant predictor of all three dietary indicators. In addition, household wealth status and administrative division are significant predictors of minimum dietary diversity and minimum acceptable diet. Children of working mothers are found to have higher odds of having minimum meal frequency and minimum acceptable diet compared to their counterparts. We find concentration indices for minimum dietary diversity as 0.21 (p<0.001), for minimum meal frequency as 0.08 (p<0.05), and for minimum acceptable diet as 0.19 (p<0.001). Wealth status of household, mother’s and father’s education levels, and exposure to mass media are the major contributing factors to these inequalities. Therefore, policymakers and other stakeholders need to give prior attention to enhancing household wealth status, empowering women, and awareness-raising initiatives to improve the feeding practices of children in Bangladesh.
Comparing Perceptions of Independence-Support Programs Among Young Individuals Preparing for Independence and Employees of Child Welfare Institutions
Authors: Kim Hyunju , Jang Jihyun
Published: August 2023

Objectives: This study aims to identify differences between the perceived importance and effectiveness of independence-support programs among young individuals preparing for independence and employees of child welfare institutions.Methods: The data were collected by surveying individuals discharged from out-of-home shelters located in Gyeongsangnam-do. Additionally, surveys were conducted on workers from childcare facilities and community (group) homes. The study identified gaps between perceptions of the importance of the program and its performance. Furthermore, an Importance-Performance Analysis (IPA) was conducted to identify selfreliance programs that should be prioritized.Results: The study, revealed significant differences in the perceived importance and performance of selfreliance programs among young individuals preparing for independence and the employees of child welfare institutions. Moreover, both groups perceived the performance of the self-reliance programs as being low compared to its importance.Conclusion: The findings show that, it is crucial to implement an effective self-reliance programs in out-ofhome shelters for young individuals preparing for independence. To achieve this, the aspects of the programs that help these young individuals prepare for self-reliance after discharge need enhancement. Further investigation is necessary to determine whether the duration and content of the facility-provided programs is helpful for these young individuals to adapt to the social life in the real world. Furthermore, it is necessary to supplement this research by organizing and implementing effective program.
The Effect of Self-Regulated Learning Behavior on Online Academic Procrastination and the Moderating Role of Parental Academic Involvement Latent Profiles Among Middle School Students
Authors: Jang Hye In , Park Ju Hee
Published: August 2023

Objectives: This study aimed to examine the effect of self-regulated learning on online academic procrastination and the moderating effects of parental academic involvement latent profile.Methods: The participants were 527 middle school students who completed questionnaires to assess online academic procrastination, self-regulated learning behavior, and parental academic involvement. The data were analyzed using descriptive statistics, Pearson’s correlation coefficients, latent profile analysis, and hierarchical regression analysis with SPSS 26.0 and Mplus 8.4.Results: First, latent profile analysis identified four groups of parental academic involvement: support and pressure-emphasizing type, encouragement and active support type, autonomy-supportive type, and lack of support and high-pressure type. Second, results revealed that higher levels of selfregulated learning behavior and being in the encouragement and active support type group; were associated with reduce online academic procrastination behavior. Furthermore, the study found that the negative impact of self-regulated learning behavior on online academic procrastination weakened for students in the lack of support and high-pressure type or the encouragement and active support type groups.Conclusion: This study highlights the significance of improving self-regulated learning behaviors in the context of online learning. Moreover, the results indicate that parents’ positive support and encouragement, coupled with high expectations for academic growth, are more effective in fostering academic success than solely applying academic pressure or offering autonomous learning support. These findings offer valuable insights for developing interventions to prevent and address online academic procrastination.
The Effect of Employed Mothers’ Proactive Personality on Parenting Behaviors: The Serial Mediating Effect of Work-Family Conflict and Marital Satisfaction
Authors: Lee So Jeong , Lee Woon Kyung
Published: August 2023

Objectives: This study investigated the individual and family characteristics that influence parenting behaviors. The concept of mothers’ proactive personality and its impact on parenting behaviors have been largely unexplored. Therefore, this study examined the direct effect of employed mothers’ proactive personality on parenting behaviors, as well as its indirect effect mediated by work-family conflict and marital satisfaction.Methods: Data from 202 full-time employed mothers with children in early childhood(aged 3-5 years) were analyzed using frequency analysis, Pearson’s correlation coefficients, and path analysis.Results: First, employed mothers’ proactive personality had a positively significant direct effect on positive parenting behaviors; however, it did not affect on negative parenting behaviors. Second, the indirect effect of employed mothers’ proactive personality on both positive and negative parenting behaviors mediated by work-family conflict was insignificant. Third, the indirect effect of employed mothers’ proactive personality on positive parenting behaviors mediated by marital satisfaction was positively significant. Finally, the serial mediating effect of employed mothers’ proactive personality on both positive and negative parenting behaviors mediated by work-family conflict and marital satisfaction was insignificant.Conclusion: Employed mothers’ proactive personality can serve as a significant factor influencing marital relationships and positive parenting behaviors. It is crucial to prioritize the creation of a supportive environment that helps employed mothers navigate various challenges arising from family and work responsibilities. Additionally, the pivotal role of marital satisfaction in fostering positive parenting behaviors among employed mothers should be underscored.
Identifying Types of Changes in Elementary School Students’ Perceived Academic Achievement Pressure and its Relation to Psycho-Emotional and Cognitive Characteristics
Authors: Hong Yea-Ji
Published: August 2023

Objectives: This study identified the latent types of changes in academic pressure perceptions among elementary school students in fourth to sixth grade. Additionally, the study investigated the relation between these changes and psycho-emotional and cognitive characteristics.Methods: Data from the 11th-13th waves of the Panel Study of Korean Children (PSKC) were used for preliminary correlation and descriptive analyses in SPSS Windows software version 23. A three-step growth mixture model in Mplus was then employed to uncover differences in psycho-social characteristics associated with perceived academic pressure change types and variations in their cognitive characteristics.Results: Four types of perceived academic achievement pressure changes were identified among elementary school students: low-level steady increase, high-level steady decrease, low-level rapid increase, and high-level rapid decrease. These change types were associated with significant differences in psycho-emotional characteristics, such as academic stress, time use satisfaction, and self-esteem. Additionally, distinctive executive function difficulties were observed between the rapid increase and decrease of academic achievement pressure change types in elementary school students.Conclusion: The study confirmed distinct academic achievement pressure perceptions among elementary school students, emphasizing the roles of psycho-emotional factors (academic stress, time use satisfaction, and self-esteem) and cognitive factors (executive function difficulties) in understanding these variations. The study also discussed implications and proposed directions for future research.
Tuning the Magnetic and Photocatalytic Properties of Wide Bandgap Metal Oxide Semiconductors for Environmental Remediation
Authors: Ayyakannu Sundaram Ganeshraja , Kanniah Rajkumar , Karthikeyan Vaithinathan
Published: August 2023

The review focuses on recent developments towards preparing room temperature ferromagnetic metal oxide semiconductors for better photocatalytic performance. Here we reported the combined study of photocatalytic and ferromagnetic properties at room temperature on metal oxides, particularly TiO2, which is rapidly an emerging field in the development of magnetism and environmental remediation. Even after decades of research in this area, the exact mechanism of the combination of ferromagnetism and photocatalysis in these materials has been not understood completely. However, some of the critical factors were hinted about the contribution to magnetism. Many reports demonstrated that oxygen vacancy and various metal doping plays a primary role in the room temperature ferromagnetism and photocatalysis in wide-band-gap metal oxides. However, it is not easy to understand the direct correlation between magnetism, oxygen vacancies, dopant concentration, and photocatalysis. This review primarily aims to encompass the recent progress of metal oxide for understanding magnetism and photocatalyst under visible light.
The Influence of Employer Brand Dimensions on the Affective Organizational Commitment of Employees in Small and Medium-Sized Enterprises
Authors: Cvjetković Matea , Babić Tihana
Published: August 2023

Employer branding is becoming a crucial talent management and communications strategy in many organizations today, given the importance of human resources as the most significant intangible asset of the company. In order to attract, recruit, and retain skilled employees, many companies systematically and proactively implement employer branding programs aimed at their existing and potential future employees. This can be challenging for small and medium-sized enterprises (SMEs) since their HR and marketing departments lack well-established processes, which can affect the commitment of employees. Thus, the aim of this research was to investigate the impact of five employer brand dimensions on affective organizational commitment, as the strongest type of organizational commitment. Data for the study was collected from 104 respondents employed in SMEs in Croatia and was empirically analyzed by applying the PLS-SEM method. The findings of the study showed that application and interest values positively influence affective organizational commitment, outlying the importance of knowledge transfer, workplace creativity, and innovation in a customer and humanitarian-oriented environment, as crucial elements for achieving affective organizational commitment. The research contributes to the existing literature on employer branding for SMEs operating in developing countries and provides guidance to owners and managers when building successful employer brands within their organizations.
Purification of Rainwater Using a Photocatalysis Technique to be Applied to Communities in Ciudad del Carmen, Campeche, Mexico
Authors: Montalvo Carlos , A. Aguilar Claudia , A. Martínez Rosa , M. Cerón Rosa , Ruiz Alejandro , Houbron Eric , C. Robles Juan
Published: August 2023

Small communities far from the municipal seat do not have access to drinking water, so many children suffer from various gastrointestinal diseases, which cause these children to grow up with nutritional deficiencies. In the state of Campeche, there are 300 sunny days. This energy can be used to install water treatment systems to make it drinkable. Therefore, a treatment system with heterogeneous photocatalysis was proposed using a zinc oxide catalyst doped with silver nanoparticles. The reactor has a metal structure with a flat plate where clay plates support the catalyst. Samples were taken every 2 h to carry out the corresponding analyses and in a period of 8 h of reaction. For the characterization of rainwater adhered to Mexican regulations. The results showed that there was 6400 NMP/100 mL for fecal coliforms at the beginning, and after 4 h, this parameter goes to <2 NMP/100 mL. Initially, the same happened for fecal coliforms; 9200 NMP/100 mL was determined. After 4 h, this parameter drops to <2 NMP/100 mL. The same behavior was observed with chlorides, hardness, and total alkalinity, which showed a tendency to decrease significantly. This confirms that the system works properly to eliminate organic compounds and purify rainwater.
Advanced Hydrogel for Physiological 3D Colonies of Pluripotent Stem Cells
Authors: Li Quan , Qi Guangyan , Susan Sun Xiuzhi
Published: August 2023

Human induced pluripotent stem cells (hiPSCs) demonstrated great potential in basic research, disease modeling, drug development, cell therapeutics, and regenerative medicine, as various distinct somatic cell types such as hepatocytes can be derived from hiPSCs. However, highly efficient hiPSC to somatic cell differentiation has not yet been achieved because of various challenging problems, one of which is less-optimal culture methods for hiPSC expansion. Conventionally, hiPSCs have been cultured as monolayers on flat surfaces, usually resulting in unstable genetic integrity, reduced pluripotency, and spontaneous differentiation after numerous passages. Recently, three-dimensional (3D) spheroids of hiPSCs have shown potential for somatic cell differentiations. However, these hiPSC spheroids are generated using 2D-cultured cells in either nonadherent U-bottom 96-well plates or agarose microarray molding plates, in which single hiPSCs are forced to aggregate into spheroids. These “aggregation molding” methods are neither typically suited for large-scale hiPSC manufacturing nor for tissue engineering. In addition, the aggregated hiPSC spheroids present limited functions compared to physiologically formed hiPSC 3D colonies. In this chapter, advanced 3D cell culture technologies will be reviewed, and comprehensive discussions and future development will be provided and suggested.
Design Affordance Does Matter: A Spotlight on Categorization and Evaluation of Hybrid Innovations by Consumers
Authors: El Amri Dhouha , Amine Abdelmajid , Besson Madeleine
Published: August 2023

In the high-tech field, we are witnessing the proliferation of innovations combining different categories of products into a single one called new hybrid products (NHP). Given the inherent particularities to their hybrid nature, ensuring that the boundaries between their categories of belonging become blurred and making their allocation to a well-defined category difficult, thus increasing the risk perceived by consumers as to the uses and performance of these multifunction products. In this study, qualitative methods are used to gain a boarder understanding of how consumers categorize new hybrid products (NHP) by articulating theories of categorization and affordance. Our results show that product affordance drives the NHP’s attribution to a category thereby reducing the uncertainty associated with the choice task. They point the relevance of the holistic perception of the NHP’s design in identifying its potential uses and the decomposed view of the design in favoring its attribution to a host category. This chapter will give hints to companies about how the integration of affordance in the design will help de-risking innovation development as affordance is involved not only in their attribution to the appropriate product category but also in their right evaluation and adoption by consumers.
Effect of 8-Weeks PNF Stretching on Muscle Strength and Neuromuscular Activity of the Hamstring Muscles
Authors: Latouf Ben Khaled Abboud , Halouani Jamel , Khalil Majd Eddine Mohamed Salah , Chtourou Hamdi
Published: August 2023

Background: Hamstring injuries are common in sports that involve rapid, forceful lengthening of the hamstring muscles, such as sprinting, jumping, and kicking. This type of injury is more likely to occur in team sports such as football and handball. Objectives: The purpose of this study was to investigate chronic effects of proprioceptive neuromuscular facilitation (PNF) stretching on muscle strength and neuromuscular activity of the hamstring muscle. Methods: Six male team sports players (age: 24.38 ± 1.94 years; height: 180.73 ± 6.05 cm; body-mass: 80.23 ± 10.42 kg) were recruited for this study. Participants completed a 2-month rehabilitation program that included three sessions per week of contract-relax (CR) PNF stretching. Neuromuscular activity and strength were evaluated by electromyography (EMG) and force sensor before and after 8 weeks of CR-PNF stretching. Results: The neuromuscular activity of the medial and lateral hamstring muscles was significantly different between pre-and post-training for the apex and area of muscle (P < 0.01). Similarly, there was a large difference between pre- and post-training for hamstring muscle strength (medial and lateral) in the contract and relax positions (P < 0.001). Conclusions: Eight weeks of contract-relax proprioceptive neuromuscular facilitation (PNF) stretching is effective in increasing neuromuscular activity and muscle strength in the hamstring muscles.
Contributions to industrial process condition forecasting applied to copper rod manufacturing process
Authors:   , Zurita Millán Daniel
Published: August 2023

Ensuring reliability and robustness of operation is one of the main concerns in industrial anufacturing processes , dueto the ever-increasing demand for improvements over the cost and quality ofthe processes outcome. In this regard , a deviation from the nominal operating behaviours implies a divergence from the optimal condition specification, anda misalignment from the nominal product quality, causing a critica! loss of potential earnings . lndeed, since a decade ago, the industrial sector has been carried out a significant effort

Asegurar la fiabilidad y la robustez es uno de los principales objetivos en la monitorización de los procesos industriales, ya que estos cada vez se encuentran sometidos a demandas de producción más elevadas a la vez que se deben bajar costes de fabricación manteniendo la calidad del producto final. En este sentido, una desviación de la operación del proceso implica una divergencia de los parámetros óptimos preestablecidos, lo que conlleva a una desviación respecto la calidad nominal del producto final, causando así un rechazo de dicho producto y una perdida en costes para la empresa. De hecho, tanto es así, que desde hace más de una década el sector industrial ha dedicado un esfuerzo considerable a la implantación de metodologías de monitorización inteligente. Dichos métodos son capaces extraer información respecto a la condición de las diferentes maquinarias y procesos involucrados en el proceso de fabricación. No obstante, esta información extraída corresponde al estado actual del proceso. Por lo que obtener información respecto a la condición futura de dicho proceso representa una mejora significativa para poder ganar tiempo de respuesta para la detección y corrección de desviaciones en la operación de dicho proceso. Por lo tanto, la combinación del conocimiento futuro del comportamiento del proceso con la consecuente evaluación de la condición del mismo, es un objetivo a cumplir para la definición de las nuevas generaciones de sistemas de monitorización de procesos industriales. En este sentido, la presente tesis tiene como objetivo la propuesta de metodologías para evaluar la condición, actual y futura, de procesos industriales. Dicha metodología debe estimar la condición de forma fiable y con una alta resolución. Por lo tanto, en esta tesis se pretende extraer la información de la condición futura a partir de un modelado, basado en series temporales, de las señales críticas del proceso, para después, en base a enfoques no lineales de preservación de la topología, fusionar dichas señales proyectadas a futuro para conocer la condición. El rendimiento y la bondad de las metodologías propuestas en la tesis han sido validadas mediante su aplicación en un proceso industrial real, concretamente, con datos de una planta de fabricación de alambrón de cobre.
Learning with nearest neighbour classifiers
Authors:   , Bermejo Sánchez Sergio
Published: August 2023

Premi extraordinari ex-aequo en l'àmbit d'Electrònica i Telecomunicacions. Convocatoria 1999 - 2000

Nearest Neighbour (NN) classifiers are one of the most celebrated algorithms in machine learning. In recent years, interest in these methods has flourished again in several fields (including statistics, machine learning and pattern recognition) since, in spite of their simplicity, they reveal as powerful non-parametric classification systems in real-world problems. The present work is mainly devoted to the development of new learning algorithms for these classifiers and is focused on the following topics:

- Development of learning algorithms for crisp and soft k-NN classifiers with large margin
- Extension and generalization of Kohonen's LVQ algorithms
- Local stabilization techniques for ensembles of NN classifiers
- Study of the finite-sample convergence of the on-line LVQ1 and k-means algorithms

Besides, a novel oriented principal component analysis (OPCA) addressed for feature
extraction in classification is introduced. The method integrates the feature extraction into the classifier and performs global training to extract those features useful for the classifier. The application of this general technique in the context of NN classifiers derives in a problem of learning their weight metric.
Modulation and control of three-phase PWM multilevel converters
Authors:   , Pou Félix Josep
Published: August 2023

La present tesi doctoral estudia els inversors trifàsics multinivell del tipus denominat de díodes de fixació (diode-clamped converters). Aquests convertidors poden generar tres o més nivells de tensió a cada fase de sortida, i normalment s'apliquen a sistemes de gran potència ja que poden treballar amb tensions majors que els inversors clàssics. L'anàlisi es centra fonamentalment en la topologia de tres nivells, tot i que també es realitzen contribucions per a convertidors de més nivells. Els principals objectius són la proposta de nous algorismes de modulació vectorial PWM de processat ràpid, l'estudi i la compensació dels efectes dels desequilibris de les tensions dels condensadors del bus de continua, i l'anàlisi de llaços de control avançat.
S'han desenvolupat diversos models que han permès obtenir resultats de simulació de les tècniques de modulació i control proposades. A més, gràcies a l'estada d'un any de l'autor al Center for Power Electronics Systems (CPES) a Virginia Tech, USA, la tesi també inclou resultats experimentals que consoliden les conclusions i metodologies presentades. Les principals contribucions es resumeixen a continuació.
Es presenta un nou algorisme de modulació vectorial PWM que aprofita simetries del diagrama vectorial per a reduir el temps de processat. S'analitzen i es quantifiquen les oscil·lacions de tensió de baixa freqüència que apareixen en el punt central dels condensadors del convertidor de tres nivells. Aquesta informació permet dimensionar els condensadors donades les especificacions d'una determinada aplicació.
L'algorisme de modulació també s'aplica a convertidors de més nivells. Pel cas concret del convertidor de quatre nivells, es comprova l'existència de corrents continus en els punts mitjos dels condensadors que fan que els sistema sigui inestable. Es determinen gràficament les zones d'inestabilitat.
Es presenta un nou i eficient algorisme de modulació vectorial feedforward en el convertidor de tres nivells que és capaç de generar tensions trifàsiques de sortida equilibrades, malgrat l'existència de desequilibris en les tensions dels condensadors.
S'estudien els efectes negatius de càrregues lineals desequilibrades i càrregues no lineals en el control de les tensions dels condensadors. Es justifica que l'existència d'un quart harmònic en els corrents de càrrega pot inestabilitzar el sistema. És determina la màxima amplitud tolerable d'aquest harmònic.
S'estudia la millora en l'equilibrat de les tensions d'una connexió de dos convertidors de tres nivells al mateix bus de continua (back-to-back connection). Un exemple d'aplicació pràctica és la conversió AC/DC/AC per a l'accionament de motors d'alterna treballant amb factor de potència unitari.
Finalment s'aplica un controlador òptim al convertidor de tres nivells treballant com a rectificador elevador (boost). El llaç de control LQR (Linear Quadratic Regulator) es simplifica donat que la tasca d'equilibrat de les tensions dels condensadors es dur a terme en el mateix modulador.
Contribución al estudio de los micropotenciales cardíacos
Authors:   , Vargas Drechsler Manuel
Published: August 2023

El objetivo principal de la tesis es el análisis y la reducción del ruido en la electrocardiografía de alta resolución con el propósito de mejorar la detección de los potenciales ventriculares tardíos. La hipótesis es que un cuidadoso análisis del ruido y de las técnicas empleadas actualmente para su reducción permitirá proponer mejoras a dichas técnicas. En otra tesis (Fernández, 1996) se estudian diversos métodos de reducción de ruido en el momento de realizar la adquisición, tales como el apantallamiento de los electrodos, la utilización de electrodos activos y las técnicas de relajación del paciente.
Nosotros nos basamos en registros adquiridos sin aplicar dichas técnicas, pues no es lo habitual en un entorno hospitalario. Por otra parte, hemos analizado y propuesto técnicas de reducción del ruido electrónico del sistema de adquisición, pues una vez aplicadas las técnicas propuestas en la mencionada tesis para la reducción de las otras fuentes de ruido, puede que el ruido electrónico sí adquiera relevancia.
Otra de las fuentes de ruido es la interferencia producida por la red de distribución eléctrica. Sin embargo, los filtros de red habituales introducen una distorsión inaceptable en la señal electrocardiográfica de alta resolución. Otro de los objetivos de la tesis será, pues, el desarrollo de un nuevo filtro para las interferencias de red que no distorsione la fase de la señal de interés y que no anule la componente de la señal a la frecuencia de red ni armónicos.
La reducción de ruido conseguida mediante promediado de señal depende de la estacionariedad del ruido, tema al que no se le ha prestado la debida atención. Otro objetivo de la tesis será, pues, el análisis de la estacionariedad del ruido, tanto para derivaciones superficiales como esofágicas. Esto nos permitirá criticar y mejorar los métodos actuales de reducción de ruido. También definiremos y estudiaremos nuevos métodos de reducción de ruido no estacionario.
Describimos brevemente el contenido de cada uno de los capítulos que siguen. El segundo capítulo está dedicado al análisis y reducción del ruido del sistema electrónico. El tercer capítulo está dedicado a la reducción de la interferencia de red. En el cuarto capítulo se analiza la estacionariedad del ruido y se proponen varios métodos de reducción de ruido no estacionario. Mediante estos métodos se puede reducir el ruido de las otras dos fuentes: el ruido de los electrodos y el ruido fisiológico (EMG). En el capítulo quinto se describe la aplicación de las técnicas desarrolladas a la detección de potenciales ventriculares tardíos. Finalmente, en el sexto capítulo se describen las conclusiones que se han obtenido.
Contribución a la mejora de resolución de los sistemas de obtención de imágenes por ultrasonidos
Authors:   , Salazar Soler Jorge
Published: August 2023

El objetivo principal de esta Tesis se centra en la mejora de la resolución axial de los sistemas de ultrasonidos basados en la medida del tiempo de vuelo y/o la recepción de ecos, utilizando soluciones de bajo coste. Se propone como excitación del transductor el uso de formas de onda simples cuyos parámetros básicos han sido obtenidos a partir del análisis de las características presentadas por uno de los pulsos acústicos emitido y recibido por el propio transductor. Esta técnica se muestra particularmente eficaz al aplicarla a transductores muy poco amortiguados, es decir, con un factor Q alto, lo que hace que sea muy adecuada para utilizarla con transductores de aire, cuyos pulsos presentan una respuesta transitoria de duración excesiva en forma de "colas de emisión".

Tras la introducción del principio de funcionamiento en que se basa la técnica de cancelación por pulso, se desarrolla la teoría necesaria para poder determinar los parámetros básicos del pulso de cancelación, tanto en el dominio temporal como en el frecuencial. Previamente se han justificado los requisitos que debe cumplir la envolvente del pulso que se desea cancelar en parte.

Se ha desarrollado un procedimiento de simulación basado en el software HSPICE para poder evaluar a priori la mejora introducida por la técnica de cancelación por pulso. Se evita así el tener que realizar medidas experimentales para determinar las características de la excitación necesaria. Los resultados obtenidos con simulación fueron contrastados con medidas experimentales viendo que existía una estrecha correlación entre ellos.

Se hace también un estudio de la excitación específica que requiere uno de los transductores utilizados en este trabajo. El objetivo de este estudio será la comparación entre los resultados aportados por la técnica de cancelación por pulso y por la técnica de excitación basada en la inversa de la respuesta impulsional del transductor. Los pulsos acústicos emitidos con esta última técnica son analizados atendiendo a criterios energéticos. Se propone un nuevo procedimiento para determinar con precisión la respuesta impulsional de un sistema que ha sido aplicado a la caracterización de transductores de ultrasonidos.

Se ha realizado un estudio sobre las mejoras introducidas en diversos sistemas de medida por ultrasonidos cuando a ellas se aplica la técnica de cancelación por pulso. El resultado es que se mejora notablemente la resolución de la medida y las prestaciones de los equipos de medida sin que ello signifique un coste adicional para el equipo.

En resumen, como contribución fundamental de este trabajo de Tesis se ha formalizado la técnica de cancelación por pulso aportando la teoría necesaria para la obtención de los parámetros básicos característicos del pulso de cancelación.
Arquitecturas y circuitos CMOS para el control, generación y procesado de señal de MEMS
Authors:   , Fernández Martínez Daniel
Published: August 2023

En esta tesis se muestran arquitecturas y circuitos CMOS para el control de actuadores electroestáticos MEMS y para la generación y procesado de las señales proveniente de microsistemas.
En el primer capítulo se introducen dos circuitos para la estimación de distancia o capacidad entre armaduras de actuadores electroestáticos y se muestran aplicaciones de los mismos, incluyendo la caracterización de la estática y dinámica de los actuadores, la detección de fallos y envejecimiento y su aplicación dentro de osciladores digitales pulsados y como parte de un sistema de actuación resonante de baja tensión.
En el segundo capítulo se muestra un estudio sobre la viabilidad de la fabricación monolítica de actuadores electroestáticos dentro del proceso CMOS utilizando un sencillo proceso de wet etching de bajo coste para liberar las estructuras.
En el tercer capítulo se presentan dos elementos translineales CMOS de alto ancho de banda y alta precisión y su aplicación como multiplicadores, divisores, filtros y como parte integrante de una celda reconfigurable con la que construir una FPAA capaz de realizar numerosas funciones del procesado analógico de señal.
En el cuarto capítulo se muestran diseños adicionales como una ley para el control de la dinámica de actuadores electroestáticos con la que se pueden ajustar eléctricamente todos los parámetros que gobiernan su movimiento y un convertidor de potencia integrado con control digital basado en una máquina de estados asíncrona.
Finalmente, en el capítulo cinco, se presentan las conclusiones finales de este trabajo.
Influència de les Interconnexions en Disseny Microelectrònic
Authors:   , Moll Echeto Francisco de Borja
Published: August 2023

Debido a los actuales niveles de integración que permite la tecnología de fabricación de circuitos integrados, las interconexiones juegan cada vez un papel más importante en el comportamiento de dichos circuitos introduciendo efectos que pueden causar errores en su funcionamiento.

Los objetivos de esta tesis son por una parte la modelación adecuada de las interconexiones en circuitos integrados, y por otra parte un estudio del efecto de las señales espureas producidas por efectos parásitos de interconexiones. Se han considerado diferentes modelos de interconexiones con parámetros distribuidos y concentrados, para determinar el rango de validez de cada modelo en función de parámetros de diseño como son longitud de la línea y características de fuente y carga de la línea. Se han realizado medidas experimentales y simulaciones para el caso de líneas sobre sustrato semiconductor para una correcta modelación de estas, observándose que el efecto de la conductancia del sustrato no hace falta incluirlo en el modelo.

Finalmente, se ha estudiado el efecto de señales espureas sobre circuitos digitales en base al concepto de curvas de propagación, que han sido calculadas teóricamente y obtenido experimentalmente para ciertos casos.
Aportació al control amb microprocessador de convertidors CC/CC
Authors:   , Bordonau Farrerons José
Published: August 2023

El objetivo deseado es la experimentación del control con microprocesador de un convertidor CC/CC, para optimizar su rendimiento. La filosofía utilizada se basa en el uso de dos políticas de control distintas para controlar el convertidor: el modo de la relación de conducción y el modo de corriente. Cada política da una dinámica distinta al sistema. Mediante el uso de un estimador predictor se escoge en cada periodo de muestreo aquel modo que maximice el rendimiento.

Las aportaciones presentadas abarcan varias áreas: a) la modelación del convertidor, presentándose un nuevo método de modelación, el método de regresión; b) el diseño de la ley de control y del estimador de estado, mediante un paquete de programas desarrollado; c) la realización del circuito de control del convertidor, que permita el modo de funcionamiento dual; d) el algoritmo de control.

Es de destacar que varias de las aportaciones realizadas son extensibles a otros sistemas, no específicamente convertidores CC/CC (puede se incluso sistemas no electrónicos).
Modulador óptico cuasiestático en la banda del infrarrojo basado en la ritf
Authors:   , Ortega Redondo Juan Antonio
Published: August 2023

Esta tesis doctoral contribuye a la búsqueda de alternativas para la sustitución de la técnica clásica demodulación de la radiación infrarroja, basada en unarueda "chopper". Esta técnica de modulación óptica, seutiliza en los sistemas de espectrofotometría e introducepartes móviles en estos equipos. Las partes móviles generan instrumentos voluminosos y de difícil transporte, puesto que los elementos mecánicos se pueden desajustar fácilmente. Trabajos recientes han conseguido eliminarlas partes móviles presentes en el sensor (tambores defiltros ópticos), pero todavía no se ha conseguido eliminar las partes móviles situadas en la fuente deinfrarrojos.De entre las diferentes alternativas planteadas, se hapropuesto profundizar en el estudio de una de ellas. Enconcreto, se profundiza en el estudio de un moduladoróptico cuasiestático basado en la Reflexión Interna TotalFrustrada, RITF. El fenómeno es ampliamente conocido,pero se ha detectado una falta de contribuciones en suaplicación a la modulación de radiación infrarroja, quetrata de resolverse abordandola en este trabajo.Uno de los puntos de estudio tratados es elfuncionamiento mecánico del modulador. Los resultadosobtenidos son vitales para realizar el control delsistema. El estudio realizado sobre la forma de laradiación de salida del modulador, es fundamental si sepretende introducir el modulador en un equipo deespectrofotometría. El último de los puntos en los quecentra su atención esta tesis doctoral, es en laobtención de algoritmos de control del modulador parapoder garantizar un funcionamiento estable del mismo
Design and analysis of a novel multilevel active-clamped power-converter
Authors:   , Nicolás Apruzzese Joan
Published: August 2023

Multilevel converter technology has been receiving increasing attention during the last years due to its important advantages compared to conventional two-level conversion. Multilevel converters reduce the voltage across each semiconductor. These converters also synthesize waveforms with better harmonic spectrum, and in most cases, increasing the efficiency of the power conversion system. However, a larger quantity of semiconductors is needed and the modulation strategy to control them becomes more complex. There are three basic multilevel converter topologies: diode clamped, flying capacitor, and cascaded H-bridge with separate dc sources. Numerous hybrid configurations combining them and other multilevel topologies have also been presented in the literature.
A novel multilevel active-clamped (MAC) topology is the subject of study of the present thesis. This topology is derived from the generalized multilevel topology by simply removing all flying capacitors. The topology can also be seen as an extension into an arbitrary number of levels of the three-level active neutral-point-clamped (ANPC) topology. The novel converter is controlled using a proper set of switching states and a switching state transition strategy, which permits to obtain the maximum benefits from the converter.
In this thesis, the performance and operating capabilities of the MAC topology are studied through comprehensive efficiency and fault-tolerance analyses.
The efficiency analysis comprises a study of power-device conduction and switching losses in the topology, followed by analytical and experimental efficiency comparisons between the MAC converter and conventional two-level converters.
In the analysis of the fault-tolerance capacity of the MAC topology both open- and short-circuit faults are considered and the analysis is carried out under single-device and two-simultaneous-device faults. Switching strategies to overcome the limitations caused by faults and topology variations to increment the fault-tolerance ability of the MAC converter are proposed.
The thesis also proposes guidelines to guarantee a proper MAC converter design and improve its performance.
Поиски единообразного решения парадоксов: иллюзия простоты
Authors: Целищев Виталий Валентинович ,   Institute of Philosophy, Russian Academy of Sciences
Published: August 2023

В статье обсуждаются предложения Ладова [Ладов, 2023] по единообразному решению классических теоретико-множественных и семантических парадоксов. Показывается, что подход Ладова сталкивается с двумя трудностями. Во-первых, метод устранения отрицания из формулировок парадоксов приводит к новым парадоксам, что демонстрируется на примере теоремы Лёба. Во-вторых, апелляция в аргументации Ладова к «схеме» Рассела», принятой Г. Пристом, не является значимой, ввиду диалетеизма Приста, согласно которому допускаются противоречия. Последнее обстоятельство препятствует единообразному решению парадоксов, предлагаемому Ладовым.
О роли существования парадоксов в программе философии математики неологицизма
Authors: Олейник Полина Ивановна ,   Institute of Philosophy, Russian Academy of Sciences
Published: August 2023

В статье обсуждаются аспекты программы философии математики неологицизма, связанные с существованием парадоксов. Отмечается недостаточная тематизированность проблематики парадоксов в программе неологицизма. Несмотря на это, использование в неологицизме методологии введения понятий с помощью принципов абстракции ограничено существованием принципов абстракции, приводящих к противоречию. Основная проблема неологицизма, «проблема плохой компании», связана с обсуждением таких принципов. Автор статьи показывает, что поиск единого критерия для демаркации приемлемых и неприемлимых принципов абстракции не приводит к необходимому результату.
О парадоксах: ответ оппонентам
Authors: Ладов Всеволод Адольфович ,   Institute of Philosophy, Russian Academy of Sciences
Published: August 2023

Автор представляет ответы оппонентам на свою статью «О принципе единого решения парадоксов» [Ладов, 2023], которая обсуждалась в рамках настоящей дискуссии. В дискуссии приняли участие как очень авторитетные отечественные философы, работающие в рамках данной проблематики, так и молодые ученые. Стоит отметить, что немалую роль в самом инициировании обсуждения данной темы сыграл недавний перевод на русский язык монографии современного философа Грэма Приста [Прист, 2022], осуществленный В.В. Целищевым. Это первая крупная работа по парадоксам современного философа с мировым именем, появившаяся на русском языке за последние годы.
Is The Collaborative Learning Training Model with An LCTL Approach to Understanding Teacher Pedagogic Competence Effective?
Authors: Masfufah Siti , Rusijono Rusijono , S. Bachri Bactiar
Published: August 2023

The Collaborative Learning (CL) Training Model through the LCTL approach at the ECCE teacher level helps understand pedagogic competencies, student characteristics and skills in compiling learning tools. This study aims to determine the effectiveness of CL training model in improving teacher pedagogic. This study used ADDIE's research design. The research sample consisted of 60 teachers in a cluster group in the Sidoarjo temple corps. Data were collected through pre-test and post-test for experimental and control groups and analyzed using independent sample t-test in the SPSS 28 software program. The results showed that (1) the CL training model with the LCTL approach was found to be able to improve teacher pedagogic. The review of experts concluded that CL syntax can be categorized as having innovative aspects based on the rationality model of teacher training with scores 3,64; (2) CL training model proved effective in improving teacher pedagogic with Paired test Samples Test shows that sig. (2- Sided) < 001 and paired sample t-test (sig. =.000) shows that there is a significant difference between pretest and postes experimental classes that carry out CL model training so that CL training models can be recommended to improve teachers' pedagogic abilities.; (3) CL training model can improve understanding of student characteristics, compile learning tools, and These results include: 1) CL training manuals through the LCTL approach and the syntax contained in the training model; 2) Application of learning tools for ECCE / kindergarten teachers and 3) Training modules which contain material on pedagogic competencies, characteristics of students and skills in compiling learning tools. This is done with the application of preparing learning tools to match the material and ease of use. From the results of the study, it can be concluded that teaching materials in the form of modules and applications of learning devices are suitable for use in training and can improve teacher competence according to their level and needs
Divan-ı Muhasebat Denetimlerinde Osmanlı Maliyesindeki Usulsüzlükler (1882-1886)
Authors: KIŞ Salih , TÜRKMEN Bilge Ceren
Published: August 2023

Zaman geçtikçe bozulmaya başlayan Osmanlı devlet yönetiminin yozlaşması, Kanuni Sultan Süleyman devrinde ivme kazanmış ve bu yozlaşma devletin askerî, idarî ve iktisadî alanları başta olmak üzere tüm birimlerine sirayet etmiştir. Osmanlı yönetim sistemi, artan yolsuzluklar nedeniyle devlete olan güvenin hızla azaldığını fark ederek bu gidişatın önünü kesmek istemiştir. Devlet, önceleri bu suça iştirak edilmesini engellemek maksadı ile kanunnameler çıkarmıştır. Kanunnamelerin çoğu devlet memurlarının kalkışacakları usulsüzlüğün cezalarına ve neticelerine atıfta bulunmaktadır. Zamanla artan yolsuzluk olayları üzerine, kanunnameler yeterli gelmemiş olacak ki devlet; usulsüzlükleri araştırmak ve denetimini sağlamak maksadı ile mali kuruluşlar inşa etmiştir. Divan-ı Muhasebat’a kadar birçok kurum gelip geçmiştir ama içlerinde en yetkili ve en mühim olanlarından biri, ilk Türk Sayıştay’ı olarak kabul edilen Divan-ı Muhasebat’tır. Divan’da usulsüzlük yapan kişilerin memur olması halinde çok daha katı cezalara çarptırılacağına dair kurallar hakimdir.
VEDAÇÃO À VIOLÊNCIA INSTITUCIONAL E À REVITIMIZAÇÃO NO CURSO DO PROCESSO
Authors: MOREIRA DE OLIVEIRA HEITOR , DIAS PAULO CEZAR
Published: August 2023

A recente divulgação pela imprensa nacional de mídias de gravações de audiências judiciais nas quais ficou evidenciado constrangimento à vítima mulher e/ou criança, trouxe luz à exigência de instrumentos e mecanismos que garantam que a participação de tais pessoas no curso do processo penal ocorra de forma humanizada e sem que lhe seja infligida nova violência, de natureza institucional. O artigo tem por objetivo analisar os dispositivos inseridos pela Lei nº 14.245/2021, destacando-se o impacto prático e os pontos divergentes de aplicação da nova lei. Emprega-se o método hipotético-dedutivo, a partir de revisão sistemática das fontes bibliográficas.