Diverging Development Paths of the Electronics Industry in Korea and Taiwan

This paper examines the process and mechanism of economic development in the Republic of Korea and Taiwan through a comparative analysis of the electronics industry in each country. The paper will show that in its initial stage of development, the electronics industry in both economies had the same type of dual structure: a domestic demand sector based on the protected domestic market, and an export sector intended to capitalize on low-wage labor for the international market. However, this dual structure in the two economies faded away after the mid-1970s as their respective indigenous export-oriented enterprises began to develop. But the primary industrial players in each economy were very different. In Korea they were comprehensive electronics manufacturers affiliated with chaebols, and in Taiwan they were small and medium-size enterprises. Differences in the two economies' development mechanisms have brought about this divergence in development paths. In Korea this mechanism has been characterized by the government's positive role and the chaebol's readiness to react to the government's leadership. In Taiwan the development mechanism has been based on the private sector independent from the government. As an extension of such diverged development paths, ICs and personal computers showed spectacular growth in Korea and Taiwan after the 1980s. The development of ICs in Korea was primarily the result of a decisive role played by the chaebol's sizable financial resources, while the competitiveness in personal computers largely reflected the agility and flexibility of Taiwanese small and medium-size enterprises.

Re-examining "difference" and "development" : a note on broadening the field of gender and development in Japan

It is the author’s position that the framework for WID/GAD, as academic field and practice concerned primarily with developing countries should be broadened so as to incorporate Japan’s own gender and development issues in its scope. Unlike other developed countries, activists and scholars in Japan rarely connected, as was also the case with the fields of women’s/gender studies and WID/GAD. However, this was not due to any lack of interest among Japanese women regarding the lives of women in developing countries. Rather the points of fissure were the notions of ‘difference’ and ‘development’ held by Japanese women. These analytical concepts were narrowly defined, which resulted in limited interaction between discourse on women’s issues in Japan and WID/GAD related to ‘other’ women. By re-examining these notions and looking more deeply into perceived differences in the local context of ‘development’, not only can we strategize on ‘differences’ in such a way that we draw strength from the very fact of being different, but also prevent ‘differences’ from being used as grounds for discrimination. As a whole, we could gain substantially by broadening the field of Gender and Development and, as such, it is imperative that this field be broadened with urgency as development itself changes in this ever-interconnected world

Optimization of urban mobility measures to achieve win-win strategies

European cities are essential in the development of Europe as they constitute the living environment of more than 60% of the population in the European Union and are drivers of the European economy – just under 85% of the EU’s gross domestic product is produced in urban areas (EC, 2007a). The car has been one of the main factors of development during the 20th century, but it is at the same time the origin of the key problems cities have to face: traffic increase. This has resulted in chronic congestion with many adverse consequences such as air pollution and noise. This loss of environmental quality is one of the reasons for urban sprawl in European cities during recent decades. But this urban sprawl at the same time worsens the environmental conditions. We must return to the dense city, but clean and competitive, and this implies reducing car use yet provides quality transport alternatives sufficient to recover and maintain the competitiveness of cities (EC, 2007a). Consequently, European cities need to establish an urban transport strategy which helps reduce their environmental problems –mainly emissions and noise – but without decreasing their trip attraction. This aspect is very important because a loss of trip attraction would result in an increase of people moving to more disperse areas, contributing towards worsening the current situation. This thesis is an attempt to contribute solutions to this problem in two ways: 1) The first is to analyze the complementarity and possible synergies of several urban transport measures aimed at improving a modal split to a more sustainable means of transport. This analysis will focus on the three aspects already mentioned: emissions, noise and attractiveness or competitiveness. 2) Once possible synergies and complementarities have been analyzed, the second objective is to propose the best combination of these measures, in terms of level of implementation, to achieve the maximum benefit with respect to the three aspects previously established: emissions, noise and attractiveness or competitiveness. Therefore, within the wide range of measures enhancing sustainable urban transport, three of them have been be selected in this thesis to establish a methodology for achieving these objectives. The analysis will be based on the region of Madrid, which is also the case study selected for this research. Las ciudades europeas son piezas fundamentales para el desarrollo europeo, ya que son el lugar de residencia de más del 60% de la población de la unión europea así como los motores de su economía – casi el 85% del PIB europeo se produce en áreas urbanas (EC, 2007a). El coche ha sido uno de los principales motores de desarrollo de las ciudades durante el siglo XX, pero se ha terminado por convertir a su vez en uno de los principales problemas con los que tiene que lidiar las ciudades: el aumento del tráfico. Esto ha derivado en unos niveles crónicos de congestión, con multitud de efectos adversos, entre los que cabe destacar la contaminación del aire y el ruido. Esta pérdida de calidad ambiental es una de las razones que ha propiciado la dispersión urbana que han experimentado las ciudades europeas en las últimas décadas. Pero esta dispersión urbana a su vez contribuye a empeorar las condiciones ambientales de las ciudades. Debemos retornar a la ciudad densa, pero limpia y competitiva, y esto implica reducir el uso del coche, pero proporcionando alternativas de transporte que permitan recuperar y mantener la competitividad de las ciudades (EC, 2007a). Por lo tanto, las ciudades europeas necesitan encontrar una estrategia de transporte urbano que ayude a reducir sus problemas medio ambientales – principalmente ruido y emisiones – pero sin hacerlas perder atractividad o competitividad. Este aspecto tiene gran importancia porque una pérdida de la misma se traduciría en un aumento de dispersión de la población hacia áreas periféricas, contribuyendo a empeorar la situación actual. Esta tesis contribuye a solucionar este problema de dos maneras: 1) La primera, analizando la complementariedad y posibles sinergias de diferentes medidas de transporte urbano orientadas a promover un reparto modal hacia modos más sostenibles. Este análisis se centrará en los tres aspectos anteriormente citados: emisiones, ruido y atractividad o competitividad. 2) Una vez las posibles sinergias y complementariedades se han analizado, el segundo objetivo es proponer la mejor combinación de estas medidas – en términos de grado de aplicación - para lograr el máximo beneficio en lo que respecta a los tres objetivos previamente establecidos. Para ello, en esta tesis se han seleccionado una serie de medidas que permitan establecer una metodología para alcanzar estos objetivos previamente definidos. El análisis se centra en la ciudad de Madrid y su área metropolitana, la cual se ha escogido como caso de estudio para realizar esta investigación.

Development of a Knowledge Base for smart screening of language disorders in primary care

Monitoring of neuro-evolutive development from birth until the age of six is a decisive factor in a child's quality of life. Early detection of development disorders in early childhood can facilitate necessary diagnosis and/or treatment. Primary-care pediatricians play a key role in early detection of development alterations as they can undertake the preventive and therapeutic actions necessary in the interest of a child's optimal development. The focus of this research paper is the construction of a Knowledge Base for smart screening aimed to assist pediatricians in processes of early referral in language disorders. The proposed model provides health professionals with a decision-making tool that supports referral processes. In this way, essential diagnostic and/or therapeutic actions are triggered for a comprehensive individual development. The resulting system was developed on the basis of an analysis and verification of 21 cases of children with language disorders.

Integration of cooperation for development in Survey Engineering curricula at the European Higher Education Area (EHEA) framework

Survey Engineering curricula involves the integration of many formal disciplines at a high level of proficiency. The Escuela de Ingenieros en Topografía, Cartografía y Geodesia at Universidad Politécnica de Madrid (Survey Engineering) has developed an intense and deep teaching on so-called Applied Land Sciences and Technologies or Land Engineering. However, new approaches are encouraged by the European Higher Education Area (EHEA). This fact requires a review of traditional teaching and methods. Furthermore, the new globalization and international approach gives new ways to this discipline to teach and learn about how to bridge gap between cultures and regions. This work is based in two main needs. On one hand, it is based on integration of basic knowledge and disciplines involved in typical Survey Engineering within Land Management. On the other, there is an urgent need to consider territory on a social and ethical basis, as far as a part of the society, culture, idiosyncrasy or economy. The integration of appropriate knowledge of the Land Management is typically dominated by civil engineers and urban planners. It would be very possible to integrate Survey Engineering and Cooperation for Development in the framework of Land Management disciplines. Cooperation for Development is a concept that has changed since beginning of its use until now. Development projects leave an impact on society in response to their beneficiaries and are directed towards self-sustainability. Furthermore, it is the true bridge to reduce gap between societies when differences are immeasurable. The concept of development has also been changing and nowadays it is not a purely economic concept. Education, science and technology are increasingly taking a larger role in what is meant by development. Moreover, it is commonly accepted that Universities should transfer knowledge to society, and the transfer of knowledge should be open to countries most in need for developing. If the importance of the country development is given by education, science and technology, knowledge transfer would be one of the most clear of ways of Cooperation for Development. Therefore, university cooperation is one of the most powerful tools to achieve it, placing universities as agents of development. In Spain, the role of universities as agents of development and cooperation has been largely strengthened. All about this work deals to how to implement both Cooperation for Development and Land Management within Survey Engineering at the EHEA framework.

Output Impedance Correction Circuit (OICC): A New Concept to Improve the Dynamic Response of DC/DC Converters with Additional Energy Path

El desarrollo da las nuevas tecnologías permite a los ingenieros llevar al límite el funcionamiento de los circuitos integrados (Integrated Circuits, IC). Las nuevas generaciones de procesadores, DSPs o FPGAs son capaces de procesar la información a una alta velocidad, con un alto consumo de energía, o esperar en modo de baja potencia con el mínimo consumo posible. Esta gran variación en el consumo de potencia y el corto tiempo necesario para cambiar de un nivel al otro, afecta a las especificaciones del Módulo de Regulador de Tensión (Voltage Regulated Module, VRM) que alimenta al IC. Además, las características adicionales obligatorias, tales como adaptación del nivel de tensión (Adaptive Voltage Positioning, AVP) y escalado dinámico de la tensión (Dynamic Voltage Scaling, DVS), imponen requisitos opuestas en el diseño de la etapa de potencia del VRM. Para poder soportar las altas variaciones de los escalones de carga, el condensador de filtro de salida del VRM se ha de sobredimensionar, penalizando la densidad de energía y el rendimiento durante la operación de DVS. Por tanto, las actuales tendencias de investigación se centran en mejorar la respuesta dinámica del VRM, mientras se reduce el tamaño del condensador de salida. La reducción del condensador de salida lleva a menor coste y una prolongación de la vida del sistema ya que se podría evitar el uso de condensadores voluminosos, normalmente implementados con condensadores OSCON. Una ventaja adicional es que reduciendo el condensador de salida, el DVS se puede realizar más rápido y con menor estrés de la etapa de potencia, ya que la cantidad de carga necesaria para cambiar la tensión de salida es menor. El comportamiento dinámico del sistema con un control lineal (Control Modo Tensión, VMC, o Control Corriente de Pico, Peak Current Mode Control, PCMC,…) está limitado por la frecuencia de conmutación del convertidor y por el tamaño del filtro de salida. La reducción del condensador de salida se puede lograr incrementando la frecuencia de conmutación, así como incrementando el ancho de banda del sistema, y/o aplicando controles avanzados no-lineales. Usando esos controles, las variables del estado se saturan para conseguir el nuevo régimen permanente en un tiempo mínimo, así como el filtro de salida, más específicamente la pendiente de la corriente de la bobina, define la respuesta de la tensión de salida. Por tanto, reduciendo la inductancia de la bobina de salida, la corriente de bobina llega más rápido al nuevo régimen permanente, por lo que una menor cantidad de carga es tomada del condensador de salida durante el tránsito. El inconveniente de esa propuesta es que el rendimiento del sistema es penalizado debido al incremento de pérdidas de conmutación y las corrientes RMS. Para conseguir tanto la reducción del condensador de salida como el alto rendimiento del sistema, mientras se satisfacen las estrictas especificaciones dinámicas, un convertidor multifase es adoptado como estándar para aplicaciones VRM. Para asegurar el reparto de las corrientes entre fases, el convertidor multifase se suele implementar con control de modo de corriente. Para superar la limitación impuesta por el filtro de salida, la segunda posibilidad para reducir el condensador de salida es aplicar alguna modificación topológica (Topologic modifications) de la etapa básica de potencia para incrementar la pendiente de la corriente de bobina y así reducir la duración de tránsito. Como el transitorio se ha reducido, una menor cantidad de carga es tomada del condensador de salida bajo el mismo escalón de la corriente de salida, con lo cual, el condensador de salida se puede reducir para lograr la misma desviación de la tensión de salida. La tercera posibilidad para reducir el condensador de salida del convertidor es introducir un camino auxiliar de energía (additional energy path, AEP) para compensar el desequilibrio de la carga del condensador de salida reduciendo consecuentemente la duración del transitorio y la desviación de la tensión de salida. De esta manera, durante el régimen permanente, el sistema tiene un alto rendimiento debido a que el convertidor principal con bajo ancho de banda es diseñado para trabajar con una frecuencia de conmutación moderada para conseguir requisitos estáticos. Por otro lado, el comportamiento dinámico durante los transitorios es determinado por el AEP con un alto ancho de banda. El AEP puede ser implementado como un camino resistivo, como regulador lineal (Linear regulator, LR) o como un convertidor conmutado. Las dos primeras implementaciones proveen un mayor ancho de banda, acosta del incremento de pérdidas durante el transitorio. Por otro lado, la implementación del convertidor computado presenta menor ancho de banda, limitado por la frecuencia de conmutación, aunque produce menores pérdidas comparado con las dos anteriores implementaciones. Dependiendo de la aplicación, la implementación y la estrategia de control del sistema, hay una variedad de soluciones propuestas en el Estado del Arte (State-of-the-Art, SoA), teniendo diferentes propiedades donde una solución ofrece más ventajas que las otras, pero también unas desventajas. En general, un sistema con AEP ideal debería tener las siguientes propiedades: 1. El impacto del AEP a las pérdidas del sistema debería ser mínimo. A lo largo de la operación, el AEP genera pérdidas adicionales, con lo cual, en el caso ideal, el AEP debería trabajar por un pequeño intervalo de tiempo, solo durante los tránsitos; la otra opción es tener el AEP constantemente activo pero, por la compensación del rizado de la corriente de bobina, se generan pérdidas innecesarias. 2. El AEP debería ser activado inmediatamente para minimizar la desviación de la tensión de salida. Para conseguir una activación casi instantánea, el sistema puede ser informado por la carga antes del escalón o el sistema puede observar la corriente del condensador de salida, debido a que es la primera variable del estado que actúa a la perturbación de la corriente de salida. De esa manera, el AEP es activado con casi cero error de la tensión de salida, logrando una menor desviación de la tensión de salida. 3. El AEP debería ser desactivado una vez que el nuevo régimen permanente es detectado para evitar los transitorios adicionales de establecimiento. La mayoría de las soluciones de SoA estiman la duración del transitorio, que puede provocar un transitorio adicional si la estimación no se ha hecho correctamente (por ejemplo, si la corriente de bobina del convertidor principal tiene un nivel superior o inferior al necesitado, el regulador lento del convertidor principal tiene que compensar esa diferencia una vez que el AEP es desactivado). Otras soluciones de SoA observan las variables de estado, asegurando que el sistema llegue al nuevo régimen permanente, o pueden ser informadas por la carga. 4. Durante el transitorio, como mínimo un subsistema, o bien el convertidor principal o el AEP, debería operar en el lazo cerrado. Implementando un sistema en el lazo cerrado, preferiblemente el subsistema AEP por su ancho de banda elevado, se incrementa la robustez del sistema a los parásitos. Además, el AEP puede operar con cualquier tipo de corriente de carga. Las soluciones que funcionan en el lazo abierto suelen preformar el control de balance de carga con mínimo tiempo, así reducen la duración del transitorio y tienen un impacto menor a las pérdidas del sistema. Por otro lado, esas soluciones demuestran una alta sensibilidad a las tolerancias y parásitos de los componentes. 5. El AEP debería inyectar la corriente a la salida en una manera controlada, así se reduce el riesgo de unas corrientes elevadas y potencialmente peligrosas y se incrementa la robustez del sistema bajo las perturbaciones de la tensión de entrada. Ese problema suele ser relacionado con los sistemas donde el AEP es implementado como un convertidor auxiliar. El convertidor auxiliar es diseñado para una potencia baja, con lo cual, los dispositivos elegidos son de baja corriente/potencia. Si la corriente no es controlada, bajo un pico de tensión de entrada provocada por otro parte del sistema (por ejemplo, otro convertidor conectado al mismo bus), se puede llegar a un pico en la corriente auxiliar que puede causar la perturbación de tensión de salida e incluso el fallo de los dispositivos del convertidor auxiliar. Sin embargo, cuando la corriente es controlada, usando control del pico de corriente o control con histéresis, la corriente auxiliar tiene el control con prealimentación (feed-forward) de tensión de entrada y la corriente es definida y limitada. Por otro lado, si la solución utiliza el control de balance de carga, el sistema puede actuar de forma deficiente si la tensión de entrada tiene un valor diferente del nominal, provocando que el AEP inyecta/toma más/menos carga que necesitada. 6. Escalabilidad del sistema a convertidores multifase. Como ya ha sido comentado anteriormente, para las aplicaciones VRM por la corriente de carga elevada, el convertidor principal suele ser implementado como multifase para distribuir las perdidas entre las fases y bajar el estrés térmico de los dispositivos. Para asegurar el reparto de las corrientes, normalmente un control de modo corriente es usado. Las soluciones de SoA que usan VMC son limitadas a la implementación con solo una fase. Esta tesis propone un nuevo método de control del flujo de energía por el AEP y el convertidor principal. El concepto propuesto se basa en la inyección controlada de la corriente auxiliar al nodo de salida donde la amplitud de la corriente es n-1 veces mayor que la corriente del condensador de salida con las direcciones apropiadas. De esta manera, el AEP genera un condensador virtual cuya capacidad es n veces mayor que el condensador físico y reduce la impedancia de salida. Como el concepto propuesto reduce la impedancia de salida usando el AEP, el concepto es llamado Output Impedance Correction Circuit (OICC) concept. El concepto se desarrolla para un convertidor tipo reductor síncrono multifase con control modo de corriente CMC (incluyendo e implementación con una fase) y puede operar con la tensión de salida constante o con AVP. Además, el concepto es extendido a un convertidor de una fase con control modo de tensión VMC. Durante la operación, el control de tensión de salida de convertidor principal y control de corriente del subsistema OICC están siempre cerrados, incrementando la robustez a las tolerancias de componentes y a los parásitos del cirquito y permitiendo que el sistema se pueda enfrentar a cualquier tipo de la corriente de carga. Según el método de control propuesto, el sistema se puede encontrar en dos estados: durante el régimen permanente, el sistema se encuentra en el estado Idle y el subsistema OICC esta desactivado. Por otro lado, durante el transitorio, el sistema se encuentra en estado Activo y el subsistema OICC está activado para reducir la impedancia de salida. El cambio entre los estados se hace de forma autónoma: el sistema entra en el estado Activo observando la corriente de condensador de salida y vuelve al estado Idle cunado el nuevo régimen permanente es detectado, observando las variables del estado. La validación del concepto OICC es hecha aplicándolo a un convertidor tipo reductor síncrono con dos fases y de 30W cuyo condensador de salida tiene capacidad de 140μF, mientras el factor de multiplicación n es 15, generando en el estado Activo el condensador virtual de 2.1mF. El subsistema OICC es implementado como un convertidor tipo reductor síncrono con PCMC. Comparando el funcionamiento del convertidor con y sin el OICC, los resultados demuestran que se ha logrado una reducción de la desviación de tensión de salida con factor 12, tanto con funcionamiento básico como con funcionamiento AVP. Además, los resultados son comparados con un prototipo de referencia que tiene la misma etapa de potencia y un condensador de salida físico de 2.1mF. Los resultados demuestran que los dos sistemas tienen el mismo comportamiento dinámico. Más aun, se ha cuantificado el impacto en las pérdidas del sistema operando bajo una corriente de carga pulsante y bajo DVS. Se demuestra que el sistema con OICC mejora el rendimiento del sistema, considerando las pérdidas cuando el sistema trabaja con la carga pulsante y con DVS. Por lo último, el condensador de salida de sistema con OICC es mucho más pequeño que el condensador de salida del convertidor de referencia, con lo cual, por usar el concepto OICC, la densidad de energía se incrementa. En resumen, las contribuciones principales de la tesis son: • El concepto propuesto de Output Impedance Correction Circuit (OICC), • El control a nivel de sistema basado en el método usado para cambiar los estados de operación, • La implementación del subsistema OICC en lazo cerrado conjunto con la implementación del convertidor principal, • La cuantificación de las perdidas dinámicas bajo la carga pulsante y bajo la operación DVS, y • La robustez del sistema bajo la variación del condensador de salida y bajo los escalones de carga consecutiva. ABSTRACT Development of new technologies allows engineers to push the performance of the integrated circuits to its limits. New generations of processors, DSPs or FPGAs are able to process information with high speed and high consumption or to wait in low power mode with minimum possible consumption. This huge variation in power consumption and the short time needed to change from one level to another, affect the specifications of the Voltage Regulated Module (VRM) that supplies the IC. Furthermore, additional mandatory features, such as Adaptive Voltage Positioning (AVP) and Dynamic Voltage Scaling (DVS), impose opposite trends on the design of the VRM power stage. In order to cope with high load-step amplitudes, the output capacitor of the VRM power stage output filter is drastically oversized, penalizing power density and the efficiency during the DVS operation. Therefore, the ongoing research trend is directed to improve the dynamic response of the VRM while reducing the size of the output capacitor. The output capacitor reduction leads to a smaller cost and longer life-time of the system since the big bulk capacitors, usually implemented with OSCON capacitors, may not be needed to achieve the desired dynamic behavior. An additional advantage is that, by reducing the output capacitance, dynamic voltage scaling (DVS) can be performed faster and with smaller stress on the power stage, since the needed amount of charge to change the output voltage is smaller. The dynamic behavior of the system with a linear control (Voltage mode control, VMC, Peak Current Mode Control, PCMC,…) is limited by the converter switching frequency and filter size. The reduction of the output capacitor can be achieved by increasing the switching frequency of the converter, thus increasing the bandwidth of the system, and/or by applying advanced non-linear controls. Applying nonlinear control, the system variables get saturated in order to reach the new steady-state in a minimum time, thus the output filter, more specifically the output inductor current slew-rate, determines the output voltage response. Therefore, by reducing the output inductor value, the inductor current reaches faster the new steady state, so a smaller amount of charge is taken from the output capacitor during the transient. The drawback of this approach is that the system efficiency is penalized due to increased switching losses and RMS currents. In order to achieve both the output capacitor reduction and high system efficiency, while satisfying strict dynamic specifications, a Multiphase converter system is adopted as a standard for VRM applications. In order to ensure the current sharing among the phases, the multiphase converter is usually implemented with current mode control. In order to overcome the limitation imposed by the output filter, the second possibility to reduce the output capacitor is to apply Topologic modifications of the basic power stage topology in order to increase the slew-rate of the inductor current and, therefore, reduce the transient duration. Since the transient is reduced, smaller amount of charge is taken from the output capacitor under the same load current, thus, the output capacitor can be reduced to achieve the same output voltage deviation. The third possibility to reduce the output capacitor of the converter is to introduce an additional energy path (AEP) to compensate the charge unbalance of the output capacitor, consequently reducing the transient time and output voltage deviation. Doing so, during the steady-state operation the system has high efficiency because the main low-bandwidth converter is designed to operate at moderate switching frequency, to meet the static requirements, whereas the dynamic behavior during the transients is determined by the high-bandwidth auxiliary energy path. The auxiliary energy path can be implemented as a resistive path, as a Linear regulator, LR, or as a switching converter. The first two implementations provide higher bandwidth, at the expense of increasing losses during the transient. On the other hand, the switching converter implementation presents lower bandwidth, limited by the auxiliary converter switching frequency, though it produces smaller losses compared to the two previous implementations. Depending on the application, the implementation and the control strategy of the system, there is a variety of proposed solutions in the State-of-the-Art (SoA), having different features where one solution offers some advantages over the others, but also some disadvantages. In general, an ideal additional energy path system should have the following features: 1. The impact on the system losses should be minimal. During its operation, the AEP generates additional losses, thus ideally, the AEP should operate for a short period of time, only when the transient is occurring; the other option is to have the AEP constantly on, but due to the inductor current ripple compensation at the output, unnecessary losses are generated. 2. The AEP should be activated nearly instantaneously to prevent bigger output voltage deviation. To achieve near instantaneous activation, the converter system can be informed by the load prior to the load-step or the system can observe the output capacitor current, which is the first system state variable that reacts on the load current perturbation. In this manner, the AEP is turned on with near zero output voltage error, providing smaller output voltage deviation. 3. The AEP should be deactivated once the new steady state is reached to avoid additional settling transients. Most of the SoA solutions estimate duration of the transient which may cause additional transient if the estimation is not performed correctly (e.g. if the main converter inductor current has higher or lower value than needed, the slow regulator of the main converter needs to compensate the difference after the AEP is deactivated). Other SoA solutions are observing state variables, ensuring that the system reaches the new steady state or they are informed by the load. 4. During the transient, at least one subsystem, either the main converter or the AEP, should be in closed-loop. Implementing a closed loop system, preferably the AEP subsystem, due its higher bandwidth, increases the robustness under system tolerances and circuit parasitic. In addition, the AEP can operate with any type of load. The solutions that operate in open loop usually perform minimum time charge balance control, thus reducing the transient length and minimizing the impact on the losses, however they are very sensitive to tolerances and parasitics. 5. The AEP should inject current at the output in a controlled manner, thus reducing the risk of high and potentially damaging currents and increasing robustness on the input voltage deviation. This issue is mainly related to the systems where AEP is implemented as auxiliary converter. The auxiliary converter is designed for small power and, as such, the MOSFETs are rated for small power/currents. If the current is not controlled, due to the some unpredicted spike in input voltage caused by some other part of the system (e.g. different converter), it may lead to a current spike in auxiliary current which will cause the perturbation of the output voltage and even failure of the switching components of auxiliary converter. In the case when the current is controlled, using peak CMC or Hysteretic Window CMC, the auxiliary converter has inherent feed-forwarding of the input voltage in current control and the current is defined and limited. Furthermore, if the solution employs charge balance control, the system may perform poorly if the input voltage has different value than the nominal, causing that AEP injects/extracts more/less charge than needed. 6. Scalability of the system to multiphase converters. As commented previously, in VRM applications, due to the high load currents, the main converters are implemented as multiphase to redistribute losses among the modules, lowering temperature stress of the components. To ensure the current sharing, usually a Current Mode Control (CMC) is employed. The SoA solutions that are implemented with VMC are limited to a single stage implementation. This thesis proposes a novel control method of the energy flow through the AEP and the main converter system. The proposed concept relays on a controlled injection of the auxiliary current at the output node where the instantaneous current value is n-1 times bigger than the output capacitor current with appropriate directions. Doing so, the AEP creates an equivalent n times bigger virtual capacitor at the output, thus reducing the output impedance. Due to the fact that the proposed concept reduces the output impedance using the AEP, it has been named the Output Impedance Correction Circuit (OICC) concept. The concept is developed for a multiphase CMC synchronous buck converter (including a single phase implementation), operating with a constant output voltage and with AVP feature. Further, it is extended to a single phase VMC synchronous buck converter. During the operation, the main converter voltage loop and the OICC subsystem capacitor current loop is constantly closed, increasing the robustness under system tolerances and circuit parasitic and allowing the system to operate with any load-current shape or pattern. According to the proposed control method, the system operates in two states: during the steady-state the system is in the Idle state and the OICC subsystem is deactivated, while during the load-step transient the system is in the Active state and the OICC subsystem is activated in order to reduce the output impedance. The state changes are performed autonomously: the system enters in the Active state by observing the output capacitor current and it returns back to the Idle state when the steady-state operation is detected by observing the state variables. The validation of the OICC concept has been done by applying it to a 30W two phase synchronous buck converter with 140μF output capacitor and with the multiplication factor n equal to 15, generating during the Active state equivalent output capacitor of 2.1mF. The OICC subsystem is implemented as single phase PCMC synchronous buck converter. Comparing the converter operation with and without the OICC the results demonstrate that the 12 times reduction of the output voltage deviation is achieved, for both basic operation and for the AVP operation. Furthermore, the results have been compared to a reference prototype which has the same power stage and a fiscal output capacitor of 2.1mF. The results show that the two systems have the same dynamic behavior. Moreover, an impact on the system losses under the pulsating load and DVS operation has been quantified and it has been demonstrated that the OICC system has improved the system efficiency, considering the losses when the system operates with the pulsating load and the DVS operation. Lastly, the output capacitor of the OICC system is much smaller than the reference design output capacitor, therefore, by applying the OICC concept the power density can be increased. In summary, the main contributions of the thesis are: • The proposed Output Impedance Correction Circuit (OICC) concept, • The system level control based on the used approach to change the states of operation, • The OICC subsystem closed-loop implementation, together with the main converter implementation, • The dynamic losses under the pulsating load and the DVS operation quantification, and • The system robustness on the capacitor impedance variation and consecutive load-steps.

Methods for the analysis of multi-scale cell dynamics from fluorescence microscopy images

La embriogénesis es el proceso mediante el cual una célula se convierte en un ser un vivo. A lo largo de diferentes etapas de desarrollo, la población de células va proliferando a la vez que el embrión va tomando forma y se configura. Esto es posible gracias a la acción de varios procesos genéticos, bioquímicos y mecánicos que interaccionan y se regulan entre ellos formando un sistema complejo que se organiza a diferentes escalas espaciales y temporales. Este proceso ocurre de manera robusta y reproducible, pero también con cierta variabilidad que permite la diversidad de individuos de una misma especie. La aparición de la microscopía de fluorescencia, posible gracias a proteínas fluorescentes que pueden ser adheridas a las cadenas de expresión de las células, y los avances en la física óptica de los microscopios han permitido observar este proceso de embriogénesis in-vivo y generar secuencias de imágenes tridimensionales de alta resolución espacio-temporal. Estas imágenes permiten el estudio de los procesos de desarrollo embrionario con técnicas de análisis de imagen y de datos, reconstruyendo dichos procesos para crear la representación de un embrión digital. Una de las más actuales problemáticas en este campo es entender los procesos mecánicos, de manera aislada y en interacción con otros factores como la expresión genética, para que el embrión se desarrolle. Debido a la complejidad de estos procesos, estos problemas se afrontan mediante diferentes técnicas y escalas específicas donde, a través de experimentos, pueden hacerse y confrontarse hipótesis, obteniendo conclusiones sobre el funcionamiento de los mecanismos estudiados. Esta tesis doctoral se ha enfocado sobre esta problemática intentando mejorar las metodologías del estado del arte y con un objetivo específico: estudiar patrones de deformación que emergen del movimiento organizado de las células durante diferentes estados del desarrollo del embrión, de manera global o en tejidos concretos. Estudios se han centrado en la mecánica en relación con procesos de señalización o interacciones a nivel celular o de tejido. En este trabajo, se propone un esquema para generalizar el estudio del movimiento y las interacciones mecánicas que se desprenden del mismo a diferentes escalas espaciales y temporales. Esto permitiría no sólo estudios locales, si no estudios sistemáticos de las escalas de interacción mecánica dentro de un embrión. Por tanto, el esquema propuesto obvia las causas de generación de movimiento (fuerzas) y se centra en la cuantificación de la cinemática (deformación y esfuerzos) a partir de imágenes de forma no invasiva. Hoy en día las dificultades experimentales y metodológicas y la complejidad de los sistemas biológicos impiden una descripción mecánica completa de manera sistemática. Sin embargo, patrones de deformación muestran el resultado de diferentes factores mecánicos en interacción con otros elementos dando lugar a una organización mecánica, necesaria para el desarrollo, que puede ser cuantificado a partir de la metodología propuesta en esta tesis. La metodología asume un medio continuo descrito de forma Lagrangiana (en función de las trayectorias de puntos materiales que se mueven en el sistema en lugar de puntos espaciales) de la dinámica del movimiento, estimado a partir de las imágenes mediante métodos de seguimiento de células o de técnicas de registro de imagen. Gracias a este esquema es posible describir la deformación instantánea y acumulada respecto a un estado inicial para cualquier dominio del embrión. La aplicación de esta metodología a imágenes 3D + t del pez zebra sirvió para desvelar estructuras mecánicas que tienden a estabilizarse a lo largo del tiempo en dicho embrión, y que se organizan a una escala semejante al del mapa de diferenciación celular y con indicios de correlación con patrones de expresión genética. También se aplicó la metodología al estudio del tejido amnioserosa de la Drosophila (mosca de la fruta) durante el cierre dorsal, obteniendo indicios de un acoplamiento entre escalas subcelulares, celulares y supracelulares, que genera patrones complejos en respuesta a la fuerza generada por los esqueletos de acto-myosina. En definitiva, esta tesis doctoral propone una estrategia novedosa de análisis de la dinámica celular multi-escala que permite cuantificar patrones de manera inmediata y que además ofrece una representación que reconstruye la evolución de los procesos como los ven las células, en lugar de como son observados desde el microscopio. Esta metodología por tanto permite nuevas formas de análisis y comparación de embriones y tejidos durante la embriogénesis a partir de imágenes in-vivo. ABSTRACT The embryogenesis is the process from which a single cell turns into a living organism. Through several stages of development, the cell population proliferates at the same time the embryo shapes and the organs develop gaining their functionality. This is possible through genetic, biochemical and mechanical factors that are involved in a complex interaction of processes organized in different levels and in different spatio-temporal scales. The embryogenesis, through this complexity, develops in a robust and reproducible way, but allowing variability that makes possible the diversity of living specimens. The advances in physics of microscopes and the appearance of fluorescent proteins that can be attached to expression chains, reporting about structural and functional elements of the cell, have enabled for the in-vivo observation of embryogenesis. The imaging process results in sequences of high spatio-temporal resolution 3D+time data of the embryogenesis as a digital representation of the embryos that can be further analyzed, provided new image processing and data analysis techniques are developed. One of the most relevant and challenging lines of research in the field is the quantification of the mechanical factors and processes involved in the shaping process of the embryo and their interactions with other embryogenesis factors such as genetics. Due to the complexity of the processes, studies have focused on specific problems and scales controlled in the experiments, posing and testing hypothesis to gain new biological insight. However, methodologies are often difficult to be exported to study other biological phenomena or specimens. This PhD Thesis is framed within this paradigm of research and tries to propose a systematic methodology to quantify the emergent deformation patterns from the motion estimated in in-vivo images of embryogenesis. Thanks to this strategy it would be possible to quantify not only local mechanisms, but to discover and characterize the scales of mechanical organization within the embryo. The framework focuses on the quantification of the motion kinematics (deformation and strains), neglecting the causes of the motion (forces), from images in a non-invasive way. Experimental and methodological challenges hamper the quantification of exerted forces and the mechanical properties of tissues. However, a descriptive framework of deformation patterns provides valuable insight about the organization and scales of the mechanical interactions, along the embryo development. Such a characterization would help to improve mechanical models and progressively understand the complexity of embryogenesis. This framework relies on a Lagrangian representation of the cell dynamics system based on the trajectories of points moving along the deformation. This approach of analysis enables the reconstruction of the mechanical patterning as experienced by the cells and tissues. Thus, we can build temporal profiles of deformation along stages of development, comprising both the instantaneous events and the cumulative deformation history. The application of this framework to 3D + time data of zebrafish embryogenesis allowed us to discover mechanical profiles that stabilized through time forming structures that organize in a scale comparable to the map of cell differentiation (fate map), and also suggesting correlation with genetic patterns. The framework was also applied to the analysis of the amnioserosa tissue in the drosophila’s dorsal closure, revealing that the oscillatory contraction triggered by the acto-myosin network organized complexly coupling different scales: local force generation foci, cellular morphology control mechanisms and tissue geometrical constraints. In summary, this PhD Thesis proposes a theoretical framework for the analysis of multi-scale cell dynamics that enables to quantify automatically mechanical patterns and also offers a new representation of the embryo dynamics as experienced by cells instead of how the microscope captures instantaneously the processes. Therefore, this framework enables for new strategies of quantitative analysis and comparison between embryos and tissues during embryogenesis from in-vivo images.

Development in Rural Areas Through Capacity Building and Education for Business

This paper is based on a case study located in Avila, central Spain. Its main objectives are to implement an entrepreneurship program and design a plan of capacity building and education for business in order to promote the development of rural areas. The methodological approach of the program is based on the use of tools that permit involving the various actors of the area from the early planning stages. The university's group that is carrying out the field work has relied on these participatory tools in very different areas and contexts for over 25 years. This has allowed the development of an advanced planning model called ?Working With People? that connects expert and experience knowledge in the territories where it is applied. With this methodological approach, the diagnosis of the territory and the design of the program's strategy has been carried out. Once completed the first phase of the program and in order to ensure the sustainability and applicability of future entrepreneurial initiatives, it is necessary to support and strengthen potential entrepreneurs through training activities and capacity building. It relies on ?How to learn from people who live there? to promote investment projects and to teach them with adequate educational skills. In this context, this article aims to study the implementation strategy of these training and capacity building activities studied from an academic perspective, as well as analyzing the potential effects of these actions in promoting entrepreneurship in the territories

A modern human pattern of dental development in Lower Pleistocene hominids from Atapuerca-TD6 (Spain)

The study of life history evolution in hominids is crucial for the discernment of when and why humans have acquired our unique maturational pattern. Because the development of dentition is critically integrated into the life cycle in mammals, the determination of the time and pattern of dental development represents an appropriate method to infer changes in life history variables that occurred during hominid evolution. Here we present evidence derived from Lower Pleistocene human fossil remains recovered from the TD6 level (Aurora stratum) of the Gran Dolina site in the Sierra de Atapuerca, northern Spain. These hominids present a pattern of development similar to that of Homo sapiens, although some aspects (e.g., delayed M3 calcification) are not as derived as that of European populations and people of European origin. This evidence, taken together with the present knowledge of cranial capacity of these and other late Early Pleistocene hominids, supports the view that as early as 0.8 Ma at least one Homo species shared with modern humans a prolonged pattern of maturation.

Broccoli sprouts: An exceptionally rich source of inducers of enzymes that protect against chemical carcinogens

Induction of phase 2 detoxication enzymes [e.g., glutathione transferases, epoxide hydrolase, NAD(P)H: quinone reductase, and glucuronosyltransferases] is a powerful strategy for achieving protection against carcinogenesis, mutagenesis, and other forms of toxicity of electrophiles and reactive forms of oxygen. Since consumption of large quantities of fruit and vegetables is associated with a striking reduction in the risk of developing a variety of malignancies, it is of interest that a number of edible plants contain substantial quantities of compounds that regulate mammalian enzymes of xenobiotic metabolism. Thus, edible plants belonging to the family Cruciferae and genus Brassica (e.g., broccoli and cauliflower) contain substantial quantities of isothiocyanates (mostly in the form of their glucosinolate precursors) some of which (e.g., sulforaphane or 4-methylsulfinylbutyl isothiocyanate) are very potent inducers of phase 2 enzymes. Unexpectedly, 3-day-old sprouts of cultivars of certain crucifers including broccoli and cauliflower contain 10–100 times higher levels of glucoraphanin (the glucosinolate of sulforaphane) than do the corresponding mature plants. Glucosinolates and isothiocyanates can be efficiently extracted from plants, without hydrolysis of glucosinolates by myrosinase, by homogenization in a mixture of equal volumes of dimethyl sulfoxide, dimethylformamide, and acetonitrile at −50°C. Extracts of 3-day-old broccoli sprouts (containing either glucoraphanin or sulforaphane as the principal enzyme inducer) were highly effective in reducing the incidence, multiplicity, and rate of development of mammary tumors in dimethylbenz(a)anthracene-treated rats. Notably, sprouts of many broccoli cultivars contain negligible quantities of indole glucosinolates, which predominate in the mature vegetable and may give rise to degradation products (e.g., indole-3-carbinol) that can enhance tumorigenesis. Hence, small quantities of crucifer sprouts may protect against the risk of cancer as effectively as much larger quantities of mature vegetables of the same variety.

Microtubule-based Endoplasmic Reticulum Motility in Xenopus laevis: Activation of Membrane-associated Kinesin during Development

The endoplasmic reticulum (ER) in animal cells uses microtubule motor proteins to adopt and maintain its extended, reticular organization. Although the orientation of microtubules in many somatic cell types predicts that the ER should move toward microtubule plus ends, motor-dependent ER motility reconstituted in extracts of Xenopus laevis eggs is exclusively a minus end-directed, cytoplasmic dynein-driven process. We have used Xenopus egg, embryo, and somatic Xenopus tissue culture cell (XTC) extracts to study ER motility during embryonic development in Xenopus by video-enhanced differential interference contrast microscopy. Our results demonstrate that cytoplasmic dynein is the sole motor for microtubule-based ER motility throughout the early stages of development (up to at least the fifth embryonic interphase). When egg-derived ER membranes were incubated in somatic XTC cytosol, however, ER tubules moved in both directions along microtubules. Data from directionality assays suggest that plus end-directed ER tubule extensions contribute ∼19% of the total microtubule-based ER motility under these conditions. In XTC extracts, the rate of ER tubule extensions toward microtubule plus ends is lower (∼0.4 μm/s) than minus end-directed motility (∼1.3 μm/s), and plus end-directed motility is eliminated by a function-blocking anti-conventional kinesin heavy chain antibody (SUK4). In addition, we provide evidence that the initiation of plus end-directed ER motility in somatic cytosol is likely to occur via activation of membrane-associated kinesin.

Tuning of activation thresholds explains flexibility in the selection and development of T cells in the thymus

Immature CD4+CD8+ thymocytes expressing T-cell antigen receptors (TCR) are selected by TCR-mediated recognition of peptides associated with major histocompatibility complex molecules on thymic stromal cells. Selection ensures reactivity of the mature cells to foreign antigens and tolerance to self. Although much has been learned about the factors that determine whether a thymocyte with a given specificity will be positively or negatively selected, selection as an aspect of the developmental process as a whole is less well-understood. Here we invoke a model in which thymocytes tune their response characteristics individually and dynamically in the course of development. Cellular development and selection are driven by receptor-mediated metabolic perturbations. Perturbation is a measure of the net intracellular change induced by external stimulation. It results from the integration of several signals and countersignals over time and therefore depends on the environment and the maturation stage of the cell. Individual cell adaptation limits the range of perturbations. Such adaptation renders thymocytes less sensitive to the level of stimulation per se, but responsive to environmental changes in that level. This formulation begins to explain the mechanisms that link developmental and selection events to each other.

Molecular heterochrony in the early development of Drosophila

Heterochrony, the relative change of developmental timing, is one of the major modes of macroevolutionary change; it identifies temporally disassociated units of developmental evolution. Here, we report the results of a fine-scale temporal study for the expression of the developmental gene hairy and morphological development in three species of Drosophila, D. melanogaster, D. simulans, and D. pseudoobscura. The results suggest that between and among closely related species, temporal displacement of ontogenetic trajectory is detected even at the earliest stage of development. Overall, D. simulans shows the earliest expression, followed by D. melanogaster, and then by D. pseudoobscura. Setting D. melanogaster as the standard, we find the approximate time to full expression is accelerated by 13 min, 48 s in D. simulans and retarded by 24 min in D. pseudoobscura. Morphologically, again with D. melanogaster setting the standard, initiation of cellularization is faster in D. simulans by 15 min, 42 s; and initiation of morphogenesis is faster in D. simulans by 18 min, 7 s. These results seem to be consistent with the finding that the approximate time to full expression of hairy is accelerated by 13 min, 48 s in D. simulans. On the other hand, the same morphological events are delayed by 5 min, 32 s, and by 11 min, 32 s, respectively, in D. pseudoobscura. These delays are small, compared with the 24-min delay in full expression. The timing changes, in total, seem consistent with continuous phyletic evolution of temporal trajectories. Finally, we speculate that epigenetic interactions of hairy expression timing and cell-cycle timing may have led to morphological differences in the terminal system of the larvae.

Loss of function of the tuberous sclerosis 2 tumor suppressor gene results in embryonic lethality characterized by disrupted neuroepithelial growth and development

Germline defects in the tuberous sclerosis 2 (TSC2) tumor suppressor gene predispose humans and rats to benign and malignant lesions in a variety of tissues. The brain is among the most profoundly affected organs in tuberous sclerosis (TSC) patients and is the site of development of the cortical tubers for which the hereditary syndrome is named. A spontaneous germline inactivation of the Tsc2 locus has been described in an animal model, the Eker rat. We report that the homozygous state of this mutation (Tsc2Ek/Ek) was lethal in mid-gestation (the equivalent of mouse E9.5–E13.5), when Tsc2 mRNA was highly expressed in embryonic neuroepithelium. During this period homozygous mutant Eker embryos lacking functional Tsc2 gene product, tuberin, displayed dysraphia and papillary overgrowth of the neuroepithelium, indicating that loss of tuberin disrupted the normal development of this tissue. Interestingly, there was significant intraspecies variability in the penetrance of cranial abnormalities in mutant embryos: the Long–Evans strain Tsc2Ek/Ek embryos displayed these defects whereas the Fisher 344 homozygous mutant embryos had normal-appearing neuroepithelium. Taken together, our data indicate that the Tsc2 gene participates in normal brain development and suggest the inactivation of this gene may have similar functional consequences in both mature and embryonic brain.

A long-range regulatory element of Hoxc8 identified by using the pClasper vector.

Hox genes are located in highly conserved clusters. The significance of this organization is unclear, but one possibility is that regulatory regions for individual genes are dispersed throughout the cluster and shared with other Hox genes. This hypothesis is supported by studies on several Hox genes in which even large genomic regions immediately surrounding the gene fail to direct the complete expression pattern in transgenic mice. In particular, previous studies have identified proximal regulatory regions that are primarily responsible for early phases of mouse Hoxc8 expression. To locate additional regulatory regions governing expression during the later periods of development, a yeast homologous recombination-based strategy utilizing the pClasper vector was employed. Using homologous recombination into pClasper, we cloned a 27-kb region around the Hoxc8 gene from a yeast artificial chromosome. A reporter gene was introduced into the coding region of the isolated gene by homologous recombination in yeast. This large fragment recapitulates critical aspects of Hoxc8 expression in transgenic mice. We show that the regulatory elements that maintain the anterior boundaries of expression in the neural tube and paraxial mesoderm are located between 11 and 19 kb downstream of the gene.