Solar-thermal and hybrid photovoltaic-thermal systems for renewable heating

Grantham Briefing Papers analyse climate change and environmental research linked to work at Imperial College London, setting it in the context of national and international policy and the future research agenda. This paper and other Grantham publications are available from: www.imperial.ac.uk/grantham/publicationsThis paper looks at the barriers and opportunities for the mass deployment of solar-thermal technologies and offers a vision for the future of solar-thermal systems. HEADLINES: -Heat constitutes about half of total global energy demand. Solar heat offers key advantages over other renewable sources for meeting this demand through distributed, integrated systems. -Solar heat is a mature sustainable energy technology capable of mass deployment. There is significant scope for increasing the installed solar heat capacity in Europe. -Only a few European countries are close to reaching the EU target of 1 m2 of solar-thermal installations per person. -One key challenge for the further development of the solar-thermal market arises from issues related to the intermittency of the solar resource, and the requirement for storage and/or backup systems. The former increases investment costs and limits adaptability. -An analysis of EU countries with good market development, suggests that obligation schemes are the best policy option for maximising installations. These do not present a direct cost to the public budget, and determine the growth of the local industry in the long term. -Solar-thermal collectors can be combined with photovoltaic (PV) modules to produce hybrid PV-thermal (PV-T) collectors. These can deliver both heat and electricity simultaneously from the same installed area and at a higher overall efficiency compared to individual solar-thermal and PV panels installed separately. --Hybrid PV-T technology provides a particularly promising solution when roof space is limited or when heat and electricity are required at the same time.Preprin

Regulación del operador dominante en las telecomunicaciones en México

regulación, telecomunicaciones, operador dominante, México

El Servicio, Factor esencial en las funcionalidades humanas

El servicio es un factor esencial de desarrollo de los procesos de interacción de los individuos como integrantes de una sociedad y es, al mismo tiempo, el elemento que los ayuda a estructurar, de forma adecuada, las relaciones que hacen en los distintos ámbitos en los que se desenvuelven, desde el plano institucional, pasando por el comercial, el político, el religioso y el laboral hasta el mismo entendido social. Todas las organizaciones, bien sean públicas o privadas, tienen una razón de ser que plantean en el enunciado de su misión corporativa. La funcionalidad que se manifiesta en dicha misión es el norte que las guía y por supuesto, es el pilar en donde se fundamentan. Es aquí donde el servicio toma su rol principal y a través de cada una de las partes que lo componen, convierte esta razón de ser institucional en la forma como se establece una posición, esperando sea siempre positiva, en el entorno llamado sociedad. Si bien es cierto que algunas nuevas tendencias traducen esta característica del servicio como un factor de diferenciación, de cara a las interacciones de índole comercial y casi siempre externas, no es menos válido que el servicio, es y debe ser, la verdadera razón de ser, tanto de los individuos como de las organizaciones.The service is an essential factor in the development of the processes of interaction of individuals as members of a society and is, at the same time, the element that helps them to structure, in an appropriate way, the relationships they make in the different areas in which that are developed, from the institutional level, through the commercial, political, religious and labor to the same social understanding. All organizations, whether public or private, have a rationale that they state in the statement of their corporate mission. The functionality manifested in this mission is the north that guides them and of course, is the pillar on which they are based. It is here that the service takes its main role and through each of the parts that compose it, converts this reason for being institutional in the way a position is established, hoping it is always positive, in the environment called society. While it is true that some new trends translate this characteristic of the service as a differentiation factor, in the face of commercial and almost always external interactions, it is no less valid than the service, it is and should be, the real reason for being , both of individuals and organizations

Rhotic variation in the Spanish spoken by Puerto Ricans in Puerto Rico and Western Massachusetts

The Spanish trill is known to present a wide range of phonetic variation in Puerto Rican Spanish (PRS), attested not only on the island but in the diaspora. Combining auditory and acoustic analysis, this research project studies acoustic data on onset /r/ in Holyoke, MA, the city with the largest per capita population of Puerto Ricans living outside the island. The aim of this dissertation is to analyze whether there is trill variation in the PR community in Holyoke, and, whether it mirrors the variation found in Puerto Rico. Special attention is paid to glottal, velar, or uvular /r/ realizations. Recent work suggests that the phonemes /r/ and /h/ have been contextually neutralized in perception, which would result in the loss of a phonemic contrast. Therefore, this project also investigates whether there is evidence for this production neutralizationusing measurements that had never been acoustically examined for this dialect (center of gravity, skewness, and kurtosis).Three experimental production tasks were designed and employed: a picture description task, a map task and a reading task. Forty-five participants performed the experimental tasks: 21 were recorded on the island and 24 in Holyoke. As a result, a total of 4,393 phonemic /r/ and /h/ were analyzed. Results indicate that there are substantial similarities in rhotic variation as well as some variation between Puerto Rico and Holyoke: (1) the same trill realizations are found and (2) the means of center of gravity, skewness and kurtosis are significantly different between /h/ and /r/ in both locations, suggesting an absence of neutralization. However,different linguistic and sociolinguistic variables affect (1) the use of the backed /r/ and (2) phonemic /h/-/r/ distinction.Findings suggest that the PR community in Holyoke tries to maintain their language, one of the most noticeable signs of immigrants’ origin, to strengthen authenticity in the same way that they keep other PR cultural experiences. The differences found suggest that, although Holyoke maintains a close bond with Puerto Rico due to the back and forth migration waves, diasporas are still changing communities which create sites of super-diversity, with different patterns as a result of these new dialect contact situations

Roadmap for the next-generation hybrid photovoltaic-thermal solar energy collectors

For hybrid photovoltaic-thermal collectors to become competitive with other types of solar energy converters, they must offer high performance at fluid outlet temperatures above 60¿°C, as is required for space heating and domestic hot water provision, which together account for nearly 50% of heat demand. A roadmap is presented of the technological advances required to achieve this goal. Strategies for reducing convective, radiative and electrical losses at elevated temperature are discussed, and an experimental characterisation of a novel transparent low-emissivity coating for photovoltaic solar cells is presented. An experimentally-validated simulation formalism is used to project the performance of different combinations of loss-reduction strategies implemented together. Finally, a techno-economic analysis is performed to predict the price points at which the hybrid technologies along the roadmap become competitive with non-hybrid photovoltaic and solar thermal technologies. The most advanced hybrid technology along the roadmap employs an evacuated cavity, a transparent low-emissivity coating, and silicon heterojunction photovoltaic cellsPeer ReviewedPostprint (author's final draft

Semejantes extraños: traducción comentada de O sujeito e seu texto, de Teresa Palazzo Nazar

Tese (doutorado) - Universidade Federal de Santa Catarina, Centro de Comunicação e Expressão, Programa de Pós-Graduação em Estudos da Tradução, Florianópolis, 2015.Com a tradução para o espanhol do livro intitulado: O sujeito e seu texto (Palazzo Nazar, 2009), neste trabalho são discutidos temas concernentes ao encontro de dos campos: os estudos da tradução e a psicanálise. Mediante a prática do comentário, se desenvolvem aspectos específicos da tradução de uma produção psicanalítica lacaniana, gestada em solo brasileiro, no que diz respeito ao léxico e ao tratamento da intertextualidade. Por acontecer entre línguas próximas, o ângulo da problemática permite revelar marcas desse trânsito e daquele deixado por línguas e epistemologias consubstanciais à psicanálise e sua história erguida graças à tradução.Abstract : Based on the process of translating O sujeito e seu texto (Palazzo Nazar, 2009) into Spanish, this work discussed issues concerning the meeting of two fields: translation studies and psychoanalysis. Through the practice of commentary, we analyze specific aspects of the translation of this text, part of the Lacanian psychoanalytic production in Brazil, in relation to the lexicon and treatment of intertextuality. As this occurs between similar languages, the angle of the problem can reveal marks of both this transit and those left by languages and epistemologies intrinsic to psychoanalysis and its history built through translation