Desing and development of a robotic platform for the evaluation of search algorithms

Plant diseases represent a major economic and environmental problem in agriculture and forestry. Upon infection, a plant develops symptoms that affect different parts of the plant causing a significant agronomic impact. As many such diseases spread in time over the whole crop, a system for early disease detection can aid to mitigate the losses produced by the plant diseases and can further prevent their spread [1]. In recent years, several mathematical algorithms of search have been proposed [2,3] that could be used as a non-invasive, fast, reliable and cost-effective methods to localize in space infectious focus by detecting changes in the profile of volatile organic compounds. Tracking scents and locating odor sources is a major challenge in robotics, on one hand because odour plumes consists of non-uniform intermittent odour patches dispersed by the wind and on the other hand because of the lack of precise and reliable odour sensors. Notwithstanding, we have develop a simple robotic platform to study the robustness and effectiveness of different search algorithms [4], with respect to specific problems to be found in their further application in agriculture, namely errors committed in the motion and sensing and to the existence of spatial constraints due to land topology or the presence of obstacles.

Research on wide-bandgap intermediate band solar cells and development of experimental techniques for their characterization

El trabajo que ha dado lugar a esta Tesis Doctoral se enmarca en la invesitagación en células solares de banda intermedia (IBSCs, por sus siglas en inglés). Se trata de un nuevo concepto de célula solar que ofrece la posibilidad de alcanzar altas eficiencias de conversión fotovoltaica. Hasta ahora, se han demostrado de manera experimental los fundamentos de operación de las IBSCs; sin embargo, esto tan sólo has sido posible en condicines de baja temperatura. El concepto de banda intermedia (IB, por sus siglas en inglés) exige que haya desacoplamiento térmico entre la IB y las bandas de valencia y conducción (VB and CB, respectivamente, por sus siglas en inglés). Los materiales de IB actuales presentan un acoplamiento térmico demasiado fuerte entre la IB y una de las otras dos bandas, lo cual impide el correcto funcionamiento de las IBSCs a temperatura ambiente. En el caso particular de las IBSCs fabricadas con puntos cuánticos (QDs, por sus siglas en inglés) de InAs/GaAs - a día de hoy, la tecnología de IBSC más estudiada - , se produce un rápido intercambio de portadores entre la IB y la CB, por dos motivos: (1) una banda prohibida estrecha (< 0.2 eV) entre la IB y la CB, E^, y (2) la existencia de niveles electrónicos entre ellas. El motivo (1) implica, a su vez, que la máxima eficiencia alcanzable en estos dispositivos es inferior al límite teórico de la IBSC ideal, en la cual E^ = 0.71 eV. En este contexto, nuestro trabajo se centra en el estudio de IBSCs de alto gap (o banda prohibida) fabricadsas con QDs, o lo que es lo mismo, QD-IBSCs de alto gap. Hemos fabricado e investigado experimentalmente los primeros prototipos de QD-IBSC en los que se utiliza AlGaAs o InGaP para albergar QDs de InAs. En ellos demostramos une distribución de gaps mejorada con respecto al caso de InAs/GaAs. En concreto, hemos medido valores de E^ mayores que 0.4 eV. En los prototipos de InAs/AlGaAs, este incremento de E^ viene acompaado de un incremento, en más de 100 meV, de la energía de activación del escape térmico. Además, nuestros dispositivos de InAs/AlGaAs demuestran conversión a la alza de tensión; es decir, la producción de una tensión de circuito abierto mayor que la energía de los fotones (dividida por la carga del electrón) de un haz monocromático incidente, así como la preservación del voltaje a temperaura ambiente bajo iluminación de luz blanca concentrada. Asimismo, analizamos el potencial para detección infrarroja de los materiales de IB. Presentamos un nuevo concepto de fotodetector de infrarrojos, basado en la IB, que hemos llamado: fotodetector de infrarrojos activado ópticamente (OTIP, por sus siglas en inglés). Nuestro novedoso dispositivo se basa en un nuevo pricipio físico que permite que la detección de luz infrarroja sea conmutable (ON y OFF) mediante iluminación externa. Hemos fabricado un OTIP basado en QDs de InAs/AlGaAs con el que demostramos fotodetección, bajo incidencia normal, en el rango 2-6/xm, activada ópticamente por un diodoe emisor de luz de 590 nm. El estudio teórico del mecanismo de detección asistido por la IB en el OTIP nos lleva a poner en cuestión la asunción de quasi-niveles de Fermi planos en la zona de carga del espacio de una célula solar. Apoyados por simuaciones a nivel de dispositivo, demostramos y explicamos por qué esta asunción no es válida en condiciones de corto-circuito e iluminación. También llevamos a cabo estudios experimentales en QD-IBSCs de InAs/AlGaAs con la finalidad de ampliar el conocimiento sobre algunos aspectos de estos dispositivos que no han sido tratados aun. En particular, analizamos el impacto que tiene el uso de capas de disminución de campo (FDLs, por sus siglas en inglés), demostrando su eficiencia para evitar el escape por túnel de portadores desde el QD al material anfitrión. Analizamos la relación existente entre el escape por túnel y la preservación del voltaje, y proponemos las medidas de eficiencia cuántica en función de la tensión como una herramienta útil para evaluar la limitación del voltaje relacionada con el túnel en QD-IBSCs. Además, realizamos medidas de luminiscencia en función de la temperatura en muestras de InAs/GaAs y verificamos que los resltados obtenidos están en coherencia con la separación de los quasi-niveles de Fermi de la IB y la CB a baja temperatura. Con objeto de contribuir a la capacidad de fabricación y caracterización del Instituto de Energía Solar de la Universidad Politécnica de Madrid (IES-UPM), hemos participado en la instalación y puesta en marcha de un reactor de epitaxia de haz molecular (MBE, por sus siglas en inglés) y el desarrollo de un equipo de caracterización de foto y electroluminiscencia. Utilizando dicho reactor MBE, hemos crecido, y posteriormente caracterizado, la primera QD-IBSC enteramente fabricada en el IES-UPM. ABSTRACT The constituent work of this Thesis is framed in the research on intermediate band solar cells (IBSCs). This concept offers the possibility of achieving devices with high photovoltaic-conversion efficiency. Up to now, the fundamentals of operation of IBSCs have been demonstrated experimentally; however, this has only been possible at low temperatures. The intermediate band (IB) concept demands thermal decoupling between the IB and the valence and conduction bands. Stateof- the-art IB materials exhibit a too strong thermal coupling between the IB and one of the other two bands, which prevents the proper operation of IBSCs at room temperature. In the particular case of InAs/GaAs quantum-dot (QD) IBSCs - as of today, the most widely studied IBSC technology - , there exist fast thermal carrier exchange between the IB and the conduction band (CB), for two reasons: (1) a narrow (< 0.2 eV) energy gap between the IB and the CB, EL, and (2) the existence of multiple electronic levels between them. Reason (1) also implies that maximum achievable efficiency is below the theoretical limit for the ideal IBSC, in which EL = 0.71 eV. In this context, our work focuses on the study of wide-bandgap QD-IBSCs. We have fabricated and experimentally investigated the first QD-IBSC prototypes in which AlGaAs or InGaP is the host material for the InAs QDs. We demonstrate an improved bandgap distribution, compared to the InAs/GaAs case, in our wide-bandgap devices. In particular, we have measured values of EL higher than 0.4 eV. In the case of the AlGaAs prototypes, the increase in EL comes with an increase of more than 100 meV of the activation energy of the thermal carrier escape. In addition, in our InAs/AlGaAs devices, we demonstrate voltage up-conversion; i. e., the production of an open-circuit voltage larger than the photon energy (divided by the electron charge) of the incident monochromatic beam, and the achievement of voltage preservation at room temperature under concentrated white-light illumination. We also analyze the potential of an IB material for infrared detection. We present a IB-based new concept of infrared photodetector that we have called the optically triggered infrared photodetector (OTIP). Our novel device is based on a new physical principle that allows the detection of infrared light to be switched ON and OFF by means of an external light. We have fabricated an OTIP based on InAs/AlGaAs QDs with which we demonstrate normal incidence photodetection in the 2-6 /xm range optically triggered by a 590 nm light-emitting diode. The theoretical study of the IB-assisted detection mechanism in the OTIP leads us to questioning the assumption of flat quasi-Fermi levels in the space-charge region of a solar cell. Based on device simulations, we prove and explain why this assumption is not valid under short-circuit and illumination conditions. We perform new experimental studies on InAs/GaAs QD-IBSC prototypes in order to gain knowledge on yet unexplored aspects of the performance of these devices. Specifically, we analyze the impact of the use of field-damping layers, and demonstrate this technique to be efficient for avoiding tunnel carrier escape from the QDs to the host material. We analyze the relationship between tunnel escape and voltage preservation, and propose voltage-dependent quantum efficiency measurements as an useful technique for assessing the tunneling-related limitation to the voltage preservation of QD-IBSC prototypes. Moreover, we perform temperature-dependent luminescence studies on InAs/GaAs samples and verify that the results are consistent with a split of the quasi-Fermi levels for the CB and the IB at low temperature. In order to contribute to the fabrication and characterization capabilities of the Solar Energy Institute of the Universidad Polite´cnica de Madrid (IES-UPM), we have participated in the installation and start-up of an molecular beam epitaxy (MBE) reactor and the development of a photo and electroluminescence characterization set-up. Using the MBE reactor, we have manufactured and characterized the first QD-IBSC fully fabricated at the IES-UPM.

The Exploration and Development of Alternative Management Strategies for Mining and Recreational Activities Atop Mount Antero and Mount White; Chaffee County, Colorado

The Mount Antero/White area is a popular prospecting area. Recent expansions in the recreation economy is drawing more visitors to the area. Consequently, visitors may be placing unsustainable pressures on the landscape. In order to help rectify this, the legal, ecological, geologic, aesthetic, recreational, historic, social, and economic character of the Antero/White area has been identified. Four feasible management alternatives have also been recognized. They are a) take no new management actions, b) prohibit motorized activities in the area, c) develop a mineralogical park, and d) a combination of options b and c. Option C has been defended, as it best balances the desires of area users with the underlying ecological and geological character of the area.

Banking Sector Soundness, Innovation, and Development: Emerging Europe and South Asia. ACES Working Papers, 2012

While most academic and practitioner researchers agree that a country’s commercial banking sector’s soundness is a very significant indicator of a country’s financial market health, there is considerably less agreement and substantial confusion surrounding what constitutes a healthy bank in the aftermath of 2007+ financial crisis. Global banks’ balance sheets, corporate governance, management compensation and bonuses, toxic assets, and risky behavior are all under scrutiny as academics and regulators alike are trying to quantify what are “healthy, safe and good practices” for these various elements of banking. The current need to quantify, measure, evaluate, and compare is driven by the desire to spot troubled banks, “bad and risky” behavior, and prevent real damage and contagion in the financial markets, investors, and tax payers as it did in the recent crisis. Moreover, future financial crisis has taken on a new urgency as vast amounts of capital flows (over $1 trillion) are being redirected to emerging markets. This study differs from existing methods in the literature as it entail designing, constructing, and validating a critical dimension of financial innovation in respect to the eight developing countries in the South Asia region as well as eight countries in emerging Europe at the country level for the period 2001 – 2008, with regional and systemic differentials taken into account. Preliminary findings reveal that higher stages of payment systems development have generated efficiency gains by reducing the settlement risk and improving financial intermediation; such efficiency gains are viewed as positive financial innovations and positively impact the banking soundness. Potential EU candidate countries: Albania; Montenegro; Serbia

Real options in the context of innovation and development policies and practices. ACES Working Papers, 2012

This paper proposes to build on previous research on the use of real options in strategic decision making (Carayannis and Sipp, 2010) and instill some real options-related concepts stemming from systems design, more particularly engineering. It also builds on previously-established concepts of strategic knowledge serendipity and arbitrage and strategic knowledge co-opetition, co-evolution and co-specialization developed by Carayannis (2009). The application of real options “in” system and real options to innovation and innovation policies demonstrate how embedded real options can more effectively be identified and therefore the decision to execute them or not more effectively made.

Germany's stance on the TTIP. Background, interests and concerns. OSW Studies 52, March 2015

Co-operation between the United States and Germany has for many years been a subject of disputes. In addition to the differences over the US engagement in the resolution of international conflicts, bilateral relations have been strained as a consequence of the so-called Snowden scandal and the unproved allegations that Chancellor Angela Merkel’s telephone was wiretapped. The Transatlantic Trade and Investment Partnership offers a chance for improving relations between Germany and the USA for the first time in many years. Companies from the two countries may benefit from the lifting of some barriers to transatlantic economic co-operation. Furthermore, the emergence of in fact an internal EU and US market, with reduced customs tariffs and harmonised legal and economic rules, will pressure the emerging economies to make their markets more open. The TTIP may create conditions for exporting US raw materials from unconventional sources to the European Union; and this will be a benefit of geopolitical significance for Germany. The German government is aware of the fact that diversification of supplies of fossil fuels will make Europe less dependent on pressure from Moscow.

Strangers among us. Non-governmental organisations in Russia. OSW COMMENTARY 2015-09-29

The situation of the third sector in Russia, i.e. the civil society structures independent from the state, is worsening on a regular basis. The Kremlin’s actions aimed at paralysing and destroying the independent non-governmental sector seen over the past four years have been presented as part of a struggle for the country’s sovereignty. This is above all a consequence of the Russian government’s efforts to take full control of the socio-political situation in the country while it also needs to deal with the geopolitical confrontation with the West and the worsening economic crisis. The policy aimed against non-governmental organisations is depriving the public of structures for self-organisation, protection of civil rights and the means of controlling the ever more authoritarian government. At the same time, the Kremlin has been depriving itself of channels of co-operation and communication with the public and antagonising the most active citizens. The restrictive measures the Kremlin has taken over the past few years with regard to NGOs prove that Russian decision-makers believe that any social initiative independent of the government may give rise to unrest, which is dangerous for the regime, and – given the economic slump – any unrest brings unnecessary political risk.

Innovation and Development in the Age of Climate Change Adaptation: Open or Closed?

Change Adaptation: Open or Closed? Paper read at the Second African International Economic Law Network Conference, 7-8 March 2013, Wits School of Law, Johannesburg, South Africa. In a time of rapid convergence of technologies, goods, services, hardware, software, the traditional classifications that informed past treaties fail to remove legal uncertainty, or advance welfare and innovation. As a result, we turn our attention to the role and needs of the public domain at the interface of existing intellectual property rights and new modes of creation, production and distribution of goods and services. The concept of open culture would have it that knowledge should be spread freely and its growth should come from further developing existing works on the basis of sharing and collaboration without the shackles of intellectual property. Intellectual property clauses find their way into regional, multilateral, bilateral and free trade agreements more often than not, and can cause public discontent and incite unrest. Many of these intellectual property clauses raise the bar on protection beyond the clauses found in the WTO Agreement on Trade-Related Aspects of Intellectual Property Rights (TRIPS). In this paper we address the question of the protection and development of the public domain in service of open innovation in accord with Article 15 of the International Covenant on Economic, Social and Cultural Rights (ICESCR) in light of the Objectives (Article 7) and Principles (Article 8) set forth in TRIPS. Once areas of divergence and reinforcement between the intellectual property regime and human rights have been discussed, we will enter into options that allow for innovation and prosperity in the global south. We then conclude by discussing possible policy developments.

A.I.D. research and development abstracts.

Description based on: Vol. 6, no. 4 (Apr. 1979); title from cover.

CIREFCA : at the crossroads between uprooted people and development in Central America /

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Migration and development : the case of Puerto Rico /

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Evaluation of operation and maintenance factors limiting municipal wastewater treatment plant performance /

Mode of access: Internet.