Local economic impacts of transportation fuel consumption /

"DOT-I-84-01."

Light alloy castings for automotive applications: The case of Al vs Mg

The economical and environmental effects of mass reduction through Al and Mg primary alloys substitutions for cast iron and steel in automotive components are discussed using MF. Ashby's penalty functions method The viability of Mg alloy substitutions for existing Al alloy cast components is also considered. The cost analysis shows that direct, equal-volume, Al alloy substitutions for cast iron and steel are the most feasible in terms of the CAFE liability, followed by substitutions involving flat panels of prescribed stiffness. When the creation of CO2 associated to the production of Al and Mg is considered, the potential gasoline savings over the lifespan of the car compensate for the intrinsic environmental burden of Al in all applications, while electrolytic Mg substitutions for cast iron and steel are feasible for equal volume and panels only. Magnesium produced by the Pidgeon thermal process appears to be too primary energy intensive to be competitive in structural applications. Magnesium substitutions for existing Al alloy beams and panels are generally unviable. The current higher recycling efficiency of Al casting alloys confers Al a significant advantage over Mg alloys.

Sviluppo e applicazione di nuovi criteri per la verifica a fatica multiassiale di componenti strutturali in leghe di acciaio e alluminio

La presente Tesi ha per oggetto lo sviluppo e la validazione di nuovi criteri per la verifica a fatica multiassiale di componenti strutturali metallici . In particolare, i nuovi criteri formulati risultano applicabili a componenti metallici, soggetti ad un’ampia gamma di configurazioni di carico: carichi multiassiali variabili nel tempo, in modo ciclico e random, per alto e basso/medio numero di cicli di carico. Tali criteri costituiscono un utile strumento nell’ambito della valutazione della resistenza/vita a fatica di elementi strutturali metallici, essendo di semplice implementazione, e richiedendo tempi di calcolo piuttosto modesti. Nel primo Capitolo vengono presentate le problematiche relative alla fatica multiassiale, introducendo alcuni aspetti teorici utili a descrivere il meccanismo di danneggiamento a fatica (propagazione della fessura e frattura finale) di componenti strutturali metallici soggetti a carichi variabili nel tempo. Vengono poi presentati i diversi approcci disponibili in letteratura per la verifica a fatica multiassiale di tali componenti, con particolare attenzione all'approccio del piano critico. Infine, vengono definite le grandezze ingegneristiche correlate al piano critico, utilizzate nella progettazione a fatica in presenza di carichi multiassiali ciclici per alto e basso/medio numero di cicli di carico. Il secondo Capitolo è dedicato allo sviluppo di un nuovo criterio per la valutazione della resistenza a fatica di elementi strutturali metallici soggetti a carichi multiassiali ciclici e alto numero di cicli. Il criterio risulta basato sull'approccio del piano critico ed è formulato in termini di tensioni. Lo sviluppo del criterio viene affrontato intervenendo in modo significativo su una precedente formulazione proposta da Carpinteri e collaboratori nel 2011. In particolare, il primo intervento riguarda la determinazione della giacitura del piano critico: nuove espressioni dell'angolo che lega la giacitura del piano critico a quella del piano di frattura vengono implementate nell'algoritmo del criterio. Il secondo intervento è relativo alla definizione dell'ampiezza della tensione tangenziale e un nuovo metodo, noto come Prismatic Hull (PH) method (di Araújo e collaboratori), viene implementato nell'algoritmo. L'affidabilità del criterio viene poi verificata impiegando numerosi dati di prove sperimentali disponibili in letteratura. Nel terzo Capitolo viene proposto un criterio di nuova formulazione per la valutazione della vita a fatica di elementi strutturali metallici soggetti a carichi multiassiali ciclici e basso/medio numero di cicli. Il criterio risulta basato sull'approccio del piano critico, ed è formulato in termini di deformazioni. In particolare, la formulazione proposta trae spunto, come impostazione generale, dal criterio di fatica multiassiale in regime di alto numero di cicli discusso nel secondo Capitolo. Poiché in presenza di deformazioni plastiche significative (come quelle caratterizzanti la fatica per basso/medio numero di cicli di carico) è necessario conoscere il valore del coefficiente efficace di Poisson del materiale, vengono impiegate tre differenti strategie. In particolare, tale coefficiente viene calcolato sia per via analitica, che per via numerica, che impiegando un valore costante frequentemente adottato in letteratura. Successivamente, per validarne l'affidabilità vengono impiegati numerosi dati di prove sperimentali disponibili in letteratura; i risultati numerici sono ottenuti al variare del valore del coefficiente efficace di Poisson. Inoltre, al fine di considerare i significativi gradienti tensionali che si verificano in presenza di discontinuità geometriche, come gli intagli, il criterio viene anche esteso al caso dei componenti strutturali intagliati. Il criterio, riformulato implementando il concetto del volume di controllo proposto da Lazzarin e collaboratori, viene utilizzato per stimare la vita a fatica di provini con un severo intaglio a V, realizzati in lega di titanio grado 5. Il quarto Capitolo è rivolto allo sviluppo di un nuovo criterio per la valutazione del danno a fatica di elementi strutturali metallici soggetti a carichi multiassiali random e alto numero di cicli. Il criterio risulta basato sull'approccio del piano critico ed è formulato nel dominio della frequenza. Lo sviluppo del criterio viene affrontato intervenendo in modo significativo su una precedente formulazione proposta da Carpinteri e collaboratori nel 2014. In particolare, l’intervento riguarda la determinazione della giacitura del piano critico, e nuove espressioni dell'angolo che lega la giacitura del piano critico con quella del piano di frattura vengono implementate nell'algoritmo del criterio. Infine, l’affidabilità del criterio viene verificata impiegando numerosi dati di prove sperimentali disponibili in letteratura.

A GUERRA JUSTA NA CRISTIANIZAÇÃO DA AMÉRICA LATINA (1492-1566): ORIGEM DO CONCEITO, DESLOCAMENTOS E RESSIGNIFICAÇÕES

Em 1492, com o objetivo de adquirir riquezas e expansão territorial, os espanhóis chegaram à América Latina. Para tanto, rapidamente implantaram o seu sistema de governo, cultura e religião. Este processo só foi possível por meio da guerra. Para legitimá-la, foi necessário a reelaboração e a inversão de um antigo conceito de guerra e a sua consequente instauração nas terras recém ocupadas. O uso do conceito de Guerra Justa na América Latina, entre os anos1492 a 1566, fundamentava-se na história das conquistas romanas, filosofia de Aristóteles, teologia de Agostinho e Tomás de Aquino, nas leis jurídicas, Escrituras Sagradas e nas armas. Ao ser aplicado nas províncias indígenas, o conceito de Guerra Justa proporcionou efeitos trágicos pela sua violência. Ocorreram mortes de inocentes, invasão das terras, posse das riquezas, escravidão, destruição da cultura e da religião dos indígenas. Diante destes fatores, as divergências e debates tornaram-se inevitáveis. Juan Ginés de Sepúlveda, o autor do Democrates Alter, tratado que hospeda o conceito de Guerra Justa, teve como opositor tanto na Espanha quanto na América Latina, o frei dominicano Bartolomé de Las Casas que lutou a favor dos indígenas frente a injustiça da guerra deflagrada pelos conquistadores espanhóis e da cristianização por meio das armas. Entre esses dois controversistas encontra-se outro teólogo-jurista, catedrático da Universidade de Salamanca, Francisco de Vitoria. Vitoria elaborou o Derecho Natural y de Gentes, obra que concedeu a Sepúlveda e Las Casas argumentos para fundamentar suas doutrinas. A julgar pelos resultados duradouros da conquista, Sepúlveda atingiu seus objetivos. A cristandade foi implantada em substituição às religiões dos nativos e os interesses políticos e econômicos dos conquistadores, entrementes, foram concretizados. Las Casas, por sua vez, ao discordar desse método, propôs, em sua obra, Del único modo de atraer a todos los pueblos a la verdadera religión, uma cristianização pacífica que se conduzisse somente por meio da pregação do evangelho e da fé cristã. Para chegarem a essa posição, ambos os controversistas analisaram as fontes e tradições literárias aristotélica, agostiniana e tomista, em especial. O projeto missionário colonial vislumbrado por Sepúlveda e Las Casas, definiu as duas hermenêuticas eclesiásticas presentes na América Latina que se estenderam até o século XIX quando aportou-se na América uma nova proposta de missão através dos protestantes.

Antigas memórias bélicas sobre Javé em Juízes 5,3-5.9-13.19-22.23 e em Habacuque 3,3-6

A imagem de Javé em Juízes 5 constitui-se nas primeiras impressões que o Israel antigo teve do seu Deus. Ela desenha a saída de Javé de sua antiga morada no Sinai para adentrar na terra da Palestina, a fim de lutar por seu povo contra a opressão cananéia. O período tribal foi o momento formativo desse antigo conceito de Javé no Antigo Testamento. Grupos israelitas reformularam o conceito de Javé promulgado pela tradição do Sinai, afirmando, assim, que Javé não é mais o Deus estático e teofânico, morador de uma montanha, mas é o Deus de Israel . E a migração da divindade de um monte para um campo de batalha não representa meramente a caminhada dessa divindade, mas representa o caminhar dos vários estágios em que Israel conceituou seu Deus. Decisivo nessas novas articulações teológicas foi o campo de batalha, que foi o moto da celebração à Javé ressalvada em Juízes 5. Javé é celebrado por seu agir histórico! A história é a mediadora entre Javé e seu povo. Ela é a via pela qual se pronuncia sobre Javé. Assim, as novas conjunturas históricas requerem novas formulações sobre Deus. A antiga memória bélica de Javé contida em Juízes 5 perpassa a história da religião de Israel, podendo ser observada também em Habacuque 3,3-6. Esse é um texto do século VII a.C. Assim, detectamos uma memória corrente na história da religião de Israel, que começou nos momentos antecedentes à da formação da monarquia (Juízes 5) e ainda pode ser notada em Habacuque, no século VII a.C. Nesse desenrolar da religião de Israel, a memória bélica sobre Javé esteve sujeita a várias mutações. Mas, essencialmente, manteve sua proposta: tornar os sujeitos da opressão promulgada pelos impérios em agentes de transformação social. O conceito bélico de Javé patrocinou as revoltas contra o despotismo social, sendo, portanto, uma forma de resistência dos grupos desprestigiados da sociedade, em Israel e Judá

Afetividade e Fluência na Interação Empresarial: Um estudo sobre Mediação

A partir de conflito interpessoal entre gestores de empresa de médio porte, esta pesquisa realiza estudo de caso com objetivo de investigar os reflexos da mediação na fluência de interação e na afetividade dentro da empresa, enfocando 19 participantes, em três níveis: diretoria, equipe da diretoria e coordenadores. Tem como sustentação teórica as abordagens de mediação: Tradicional de Harvard; Transformativa; Narrativo-Circular e Facilitação, delineadas a partir do modelo dos sistemas dinâmicos da Teoria da Complexidade. Após caracterização inicial da empresa, utiliza-se de técnicas de pré-mediação, mediação e facilitação em grupo, analisando-as qualitativamente. Com preocupação sobre a racionalidade dos resultados sobre os reflexos do trabalho de mediação, compõe questionário sobre fluência de interação e afetividade na empresa, QFI. Os resultados do questionário comprovam os da análise da mediação, sendo que 51% dos funcionários assinalam alterações positivas na interação e na afetividade na empresa como um todo. Os pontos nevrálgicos, apontados pelos participantes como reformulados na mediação referem-se a: Autoritarismo; Muita Pressão; Falta Transparência; Co-Responsável; Cisão entre as áreas Administrativa e Técnica (Cisão AA-AT); Centralização e Escuta Insuficiente. Os dados indicam uma abertura sistêmica na tomada de consciência dos conflitos, associada a uma maior responsabilidade conjunta em tentar resolvê-los, através do gerenciamento integrado e dinâmico de competências individuais, intra e inter-grupais na empresa. O estudo considera, portanto, que a mediação pode ser vista como uma abordagem alternativa de resolução de conflitos, com resultados positivos ao meio organizacional. Devido ao fato de as técnicas de mediação não estarem ainda muito difundidas em nossa realidade, recomenda a necessidade de novas pesquisas , diversificando seu foco em empresas de vários tamanhos e segmentos.

Alcohols and other oxygenates in automotive fuels

The aim of this research was to assess the effect of oxygenated hydrocarbons on the knocking characteristics of an engine when blended with low-leaded gasoline. Alcohols, ethers, esters and ketones were tested individually and in various combinations up to an oxygen content of 4% wt/wt in a blend with Series F-7 gasoline of 90, 92, 94 and 96 RON. Tests were carried out at wide open throttle, constant speed and standard timing setting. Engine speed was varied using a dynamometer and knock was detected by two piezoelectric transducers, one on the cylinder head monitoring all four cylinders and one monitoring the cylinder most prone to knock. The engine speeds associated with trace and light knock of a continuous nature were noted. Curves were produced for each oxygenate blend of base RON used against engine speed for the two knock conditions which were compared with those produced using pure Series F-7 fuels. From this a suggested RON of the blend was derived. RON increase was less when using a higher RON base fuel in the blend. Most individual oxygenates showed similar effects in similar concentrations when their oxygen content was comparable. Blends containing more than one oxygenate showed some variation with methanol/MTBE/3 methylbutan-2-one and methanol/MTBE/4 methyl pentan-2-one knocking less than expected and methanol/MTBE/TBA also showing good knock resistance. Further tests to optimise initial findings suggested a blend of methanol and MTBE to be superior although partial replacement of MTBE by 4 methyl pentan-2-one resulted in a fuel of comparable performance. Exhaust emissions were tested for a number of oxygenated blends in 2-star gasoline. 2-star and 4-star fuels were also tested for reference. All oxygenate blends reduced carbon monoxide emissions as expected and hydrocarbon emissions were also reduced. The largest reduction in carbon monoxide occurred using a 14.5 % (1 : 1 : 1) methanol/MTBE/4 methyl pentan-2-one blend. Hydrocarbon emissions were most markedly reduced by a blend containing 25.5 % 4 methyl pentan-2-one. Power output was tested for the blends and indicated a maximum increase of about 5 % at low engine speeds. The most advantageous blends were methanol/4 methyl pentan-2-one (6 : 5) 11% in 2-star and methanol/MTBE/4 methyl pentan-2-one (6 : 3 : 2) 11% in 2-star. In conclusion methanol/MTBE (6 : 5) and (5 : 5), and various combinations of methanol/MTBE/4 methyl pentan-2-one, notably (6 : 3 : 2) gave good results in all tests conducted. CFR testing of these blends showed them to increase both RON and MON substantially.

The acceptability of alcohol fuels for automobile engines

The aim of this project was to carry out an investigastion into suitable alternatives to gasoline for use in modern automobiles. The fuel would provide the western world with a means of extending the natural gasoline resources and the third world a way of cutting down their dependence on the oil producing countries for their energy supply. Alcohols, namely methanol and ethanol, provide this solution. They can be used as gasoline extenders or as fuels on their own.In order to fulfil the aims of the project a literature study was carried out to investigate methods and costs of producing these fuels. An experimental programme was then set up in which the performance of the alcohols was studied on a conventional engine. The engine used for this purpose was the Fiat 127 930cc four cylinder engine. This engine was used because of its popularity in the European countries. The Weber fixed jet carburettor, since it was designed to be used with gasoline, was adapted so that the alcohol fuels and the blends could be used in the most efficient way. This was mainly to take account of the lower heat content of the alcohols. The adaptation of the carburettor was in the form of enlarging the main metering jet. Allowances for the alcohol's lower specfic gravity were made during fuel metering.Owing to the low front end volatility of methanol and ethanol, it was expected that `start up' problems would occur. An experimental programme was set up to determine the temperature range for a minimum required percentage `take off' that would ease start-up since it was determined that a `take off' of about 5% v/v liquid in the vapour phase would be sufficient for starting. Additions such as iso-pentane and n-pentane were used to improve the front end volatility. This proved to be successful.The lower heat content of the alcohol fuels also meant that a greater charge of fuel would be required. This was seen to pose further problems with fuel distribution from the carburettor to the individual cylinders on a multicylinder engine. Since it was not possible to modify the existing manifold on the Fiat 127 engine, experimental tests on manifold geometry were carried out using the Ricardo E6 single cylinder variable compression engine. Results from these tests showed that the length, shape and cross-sectional area of the manifold play an important part in the distribution of the fuel entering the cylinder, ie. vapour phase, vapour/small liquid droplet/liquid film phase, vapour/large liquid droplet/liquid film phase etc.The solvent properties of the alcohols and their greater electrical conductivity suggested that the materials used on the engine would be prone to chemical attack. In order to determine the type and rate of chemical attack, an experimental programme was set up whereby carburettor and other components were immersed in the alcohols and in blends of alcohol with gasoline. The test fuels were aerated and in some instances kept at temperatures ranging from 50oC to 90oC. Results from these tests suggest that not all materials used in the conventional engine are equally suitable for use with alcohols and alcohol/gasoline blends. Aluminium for instance was severely attacked by methanol causing pitting and pin-holing in the surface.In general this whole experimental programme gave valuable information on the acceptability of substitute fuels. While the long term effects of alcohol use merit further study, it is clear that methanol and ethanol will be increasingly used in place of gasoline.

Technical and economic simulation of biomass pyrolysis processes for fuels and electricity

There is considerable concern over the increased effect of fossil fuel usage on the environment and this concern has resulted in an effort to find alternative, environmentally friendly energy sources. Biomass is an available alternative resource which may be converted by flash pyrolysis to produce a crude liquid product that can be used directly to substitute for conventional fossil fuels or upgraded to a higher quality fuel. Both the crude and upgraded products may be utilised for power generation. A computer program, BLUNT, has been developed to model the flash pyrolysis of biomass with subsequent upgrading, refining or power production. The program assesses and compares the economic and technical opportunities for biomass thermochemical conversion on the same basis. BLUNT works by building up a selected processing route from a number of process steps through which the material passes sequentially. Each process step has a step model that calculates the mass and energy balances, the utilities usage and the capital cost for that step of the process. The results of the step models are combined to determine the performance of the whole conversion route. Sample results from the modelling are presented in this thesis. Due to the large number of possible combinations of feeds, conversion processes, products and sensitivity analyses a complete set of results is impractical to present in a single publication. Variation of the production costs for the available products have been illustrated based on the cost of a wood feedstock. The effect of selected macroeconomic factors on the production costs of bio-diesel and gasoline are also given.

Technoeconomic modelling of coal conversion processes for liquid fuel production

Since the oil crisis of 1973 considerable interest has been shown in the production of liquid fuels from alternative sources. In particular processes utilizing coal as the feedstock have received considerable interest. These processes can be divided into direct and indirect liquefaction and pyrolysis. This thesis describes the modelling of indirect coal liquefaction processes for the purpose of performing technical and economic assessment of the production of liquid fuels from coal and lignite, using a variety of gasification and synthesis gas liquefaction technologies. The technologies were modeled on a 'step model' basis where a step is defined as a combination of individual unit operations which together perform a significant function on the process streams, such as a methanol synthesis step or a gasification and physical gas cleaning step. Sample results of the modelling, covering a wide range of gasifiers, liquid synthesis processes and products are presented in this thesis. Due to the large number of combinations of gasifier, liquid synthesis processes, products and economic sensitivity cases, a complete set of results is impractical to present in a single publication. The main results show that methanol is the cheapest fuel to produce from coal followed by fuel alcohol, diesel from the Shell Middle Distillate Synthesis process,gasoline from Mobil Methanol to Gasoline (MTG) process, diesel from the Mobil Methanol Olefins Gasoline Diesel (MOGD) process and finally gasoline from the same process. Some variation in production costs of all the products was shown depending on type of gasifier chosen and feedstock.

Trainer talk:structures of interaction in teacher training classrooms

The subject of this research is interaction and language use in an institutional context, the teacher training classroom. Trainer talk is an interactional accomplishment and the research question is: what structures of talk-in-interaction characterise trainer talk in this institutional setting? While there has been research into other kinds of classroom and into other kinds of institutional talk, this study is the first on trainer discourse. The study takes a Conversation Analysis approach to studying institutional interaction and aims to identify the main structures of sequential organization that characterize teacher trainer talk as well as the tasks and identities that are accomplished in it. The research identifies three main interactional contexts in which trainer talk is done: expository, exploratory and experiential. It describes the main characteristics of each and how they relate to each other. Expository sequences are the predominant interactional contexts for trainer talk. But the research findings show that these contexts are flexible and open to the embedding of the other two contexts. All three contexts contribute to the main institutional goal of teaching teachers how to teach. Trainer identity is related to the different sequential contexts. Three main forms of identity in interaction are evidenced in the interactional contexts: the trainer as trainer, the trainer as teacher and the trainer as colleague. Each of them play an important role in teacher trainer pedagogy. The main features of trainer talk as a form of institutional talk are characterised by the following interactional properties: 1. Professional discourse is both the vehicle and object of instruction - the articulation of reflection on experience. 2. There is a reflexive relationship between pedagogy and interaction. 3. The professional discourse that is produced by trainees is not evaluated by trainers but, rather, reformulated to give it relevant precision in terms of accuracy and appropriacy.

Pyrolysis liquids and gases as alternative fuels in internal combustion engines:a review

Liquids and gases produced through biomass pyrolysis have potential as renewable fuels to replace fossil fuels in conventional internal combustion engines. This review compares the properties of pyrolysis fuels, produced from a variety of feedstocks and using different pyrolysis techniques, against those of fossil fuels. High acidity, the presence of solid particles, high water content, high viscosity, storage and thermal instability, and low energy content are typical characteristics of pyrolysis liquids. A survey of combustion, performance and exhaust emission results from the use of pyrolysis liquids (both crude and up-graded) in compression ignition engines is presented. With only a few exceptions, most authors have reported difficulties associated with the adverse properties of pyrolysis liquids, including: corrosion and clogging of the injectors, long ignition delay and short combustion duration, difficulty in engine start-up, unstable operation, coking of the piston and cylinders and subsequent engine seizure. Pyrolysis gas can be used more readily, either in spark ignition or compression ignition engines; however, NO reduction techniques are desirable. Various approaches to improve the properties of pyrolysis liquids are discussed and a comparison of the properties of up-graded vs. crude pyrolysis liquid is included. Further developments in up-gradation techniques, such as hydrocracking and bio-refinery approaches, could lead to the production of green diesel and green gasoline. Modifications required to engines for use with pyrolysis liquids, for example in the fuel supply and injection systems, are discussed. Storage stability and economic issues are also reviewed. Our study presents recent progress and important R&D areas for successful future use of pyrolysis fuels in internal combustion engines.

Techno-economic assessment and uncertainty analysis of thermochemical processes for second generation biofuels

Biomass-To-Liquid (BTL) is one of the most promising low carbon processes available to support the expanding transportation sector. This multi-step process produces hydrocarbon fuels from biomass, the so-called “second generation biofuels” that, unlike first generation biofuels, have the ability to make use of a wider range of biomass feedstock than just plant oils and sugar/starch components. A BTL process based on gasification has yet to be commercialized. This work focuses on the techno-economic feasibility of nine BTL plants. The scope was limited to hydrocarbon products as these can be readily incorporated and integrated into conventional markets and supply chains. The evaluated BTL systems were based on pressurised oxygen gasification of wood biomass or bio-oil and they were characterised by different fuel synthesis processes including: Fischer-Tropsch synthesis, the Methanol to Gasoline (MTG) process and the Topsoe Integrated Gasoline (TIGAS) synthesis. This was the first time that these three fuel synthesis technologies were compared in a single, consistent evaluation. The selected process concepts were modelled using the process simulation software IPSEpro to determine mass balances, energy balances and product distributions. For each BTL concept, a cost model was developed in MS Excel to estimate capital, operating and production costs. An uncertainty analysis based on the Monte Carlo statistical method, was also carried out to examine how the uncertainty in the input parameters of the cost model could affect the output (i.e. production cost) of the model. This was the first time that an uncertainty analysis was included in a published techno-economic assessment study of BTL systems. It was found that bio-oil gasification cannot currently compete with solid biomass gasification due to the lower efficiencies and higher costs associated with the additional thermal conversion step of fast pyrolysis. Fischer-Tropsch synthesis was the most promising fuel synthesis technology for commercial production of liquid hydrocarbon fuels since it achieved higher efficiencies and lower costs than TIGAS and MTG. None of the BTL systems were competitive with conventional fossil fuel plants. However, if government tax take was reduced by approximately 33% or a subsidy of £55/t dry biomass was available, transport biofuels could be competitive with conventional fuels. Large scale biofuel production may be possible in the long term through subsidies, fuels price rises and legislation.

Uses of frontier efficiency methodologies and multi-criteria decision making for performance measurement in the energy sector

Guest editorial Ali Emrouznejad is a Senior Lecturer at the Aston Business School in Birmingham, UK. His areas of research interest include performance measurement and management, efficiency and productivity analysis as well as data mining. He has published widely in various international journals. He is an Associate Editor of IMA Journal of Management Mathematics and Guest Editor to several special issues of journals including Journal of Operational Research Society, Annals of Operations Research, Journal of Medical Systems, and International Journal of Energy Management Sector. He is in the editorial board of several international journals and co-founder of Performance Improvement Management Software. William Ho is a Senior Lecturer at the Aston University Business School. Before joining Aston in 2005, he had worked as a Research Associate in the Department of Industrial and Systems Engineering at the Hong Kong Polytechnic University. His research interests include supply chain management, production and operations management, and operations research. He has published extensively in various international journals like Computers & Operations Research, Engineering Applications of Artificial Intelligence, European Journal of Operational Research, Expert Systems with Applications, International Journal of Production Economics, International Journal of Production Research, Supply Chain Management: An International Journal, and so on. His first authored book was published in 2006. He is an Editorial Board member of the International Journal of Advanced Manufacturing Technology and an Associate Editor of the OR Insight Journal. Currently, he is a Scholar of the Advanced Institute of Management Research. Uses of frontier efficiency methodologies and multi-criteria decision making for performance measurement in the energy sector This special issue aims to focus on holistic, applied research on performance measurement in energy sector management and for publication of relevant applied research to bridge the gap between industry and academia. After a rigorous refereeing process, seven papers were included in this special issue. The volume opens with five data envelopment analysis (DEA)-based papers. Wu et al. apply the DEA-based Malmquist index to evaluate the changes in relative efficiency and the total factor productivity of coal-fired electricity generation of 30 Chinese administrative regions from 1999 to 2007. Factors considered in the model include fuel consumption, labor, capital, sulphur dioxide emissions, and electricity generated. The authors reveal that the east provinces were relatively and technically more efficient, whereas the west provinces had the highest growth rate in the period studied. Ioannis E. Tsolas applies the DEA approach to assess the performance of Greek fossil fuel-fired power stations taking undesirable outputs into consideration, such as carbon dioxide and sulphur dioxide emissions. In addition, the bootstrapping approach is deployed to address the uncertainty surrounding DEA point estimates, and provide bias-corrected estimations and confidence intervals for the point estimates. The author revealed from the sample that the non-lignite-fired stations are on an average more efficient than the lignite-fired stations. Maethee Mekaroonreung and Andrew L. Johnson compare the relative performance of three DEA-based measures, which estimate production frontiers and evaluate the relative efficiency of 113 US petroleum refineries while considering undesirable outputs. Three inputs (capital, energy consumption, and crude oil consumption), two desirable outputs (gasoline and distillate generation), and an undesirable output (toxic release) are considered in the DEA models. The authors discover that refineries in the Rocky Mountain region performed the best, and about 60 percent of oil refineries in the sample could improve their efficiencies further. H. Omrani, A. Azadeh, S. F. Ghaderi, and S. Abdollahzadeh presented an integrated approach, combining DEA, corrected ordinary least squares (COLS), and principal component analysis (PCA) methods, to calculate the relative efficiency scores of 26 Iranian electricity distribution units from 2003 to 2006. Specifically, both DEA and COLS are used to check three internal consistency conditions, whereas PCA is used to verify and validate the final ranking results of either DEA (consistency) or DEA-COLS (non-consistency). Three inputs (network length, transformer capacity, and number of employees) and two outputs (number of customers and total electricity sales) are considered in the model. Virendra Ajodhia applied three DEA-based models to evaluate the relative performance of 20 electricity distribution firms from the UK and the Netherlands. The first model is a traditional DEA model for analyzing cost-only efficiency. The second model includes (inverse) quality by modelling total customer minutes lost as an input data. The third model is based on the idea of using total social costs, including the firm’s private costs and the interruption costs incurred by consumers, as an input. Both energy-delivered and number of consumers are treated as the outputs in the models. After five DEA papers, Stelios Grafakos, Alexandros Flamos, Vlasis Oikonomou, and D. Zevgolis presented a multiple criteria analysis weighting approach to evaluate the energy and climate policy. The proposed approach is akin to the analytic hierarchy process, which consists of pairwise comparisons, consistency verification, and criteria prioritization. In the approach, stakeholders and experts in the energy policy field are incorporated in the evaluation process by providing an interactive mean with verbal, numerical, and visual representation of their preferences. A total of 14 evaluation criteria were considered and classified into four objectives, such as climate change mitigation, energy effectiveness, socioeconomic, and competitiveness and technology. Finally, Borge Hess applied the stochastic frontier analysis approach to analyze the impact of various business strategies, including acquisition, holding structures, and joint ventures, on a firm’s efficiency within a sample of 47 natural gas transmission pipelines in the USA from 1996 to 2005. The author finds that there were no significant changes in the firm’s efficiency by an acquisition, and there is a weak evidence for efficiency improvements caused by the new shareholder. Besides, the author discovers that parent companies appear not to influence a subsidiary’s efficiency positively. In addition, the analysis shows a negative impact of a joint venture on technical efficiency of the pipeline company. To conclude, we are grateful to all the authors for their contribution, and all the reviewers for their constructive comments, which made this special issue possible. We hope that this issue would contribute significantly to performance improvement of the energy sector.

The idea of the hybrid text in translation revisited

This concluding chapter provides responses to some of the issues raised in the individual chapters, highlighting similarities and differences in the interpretation of the concept of the hybrid text. The questions dealt with here concern the notion of hybridity and the definition of hybrid text; the contexts in which hybrid texts emerge; the functions of hybrid texts; the various levels at which hybrid phenomena manifest themselves; the genres to which the notion of the hybrid text applies; the effects of hybrid texts; and the status of a hybrid text in Translation Studies. It is concluded that the phenomenon of the hybrid text involves greater complexity than had initially been defined in the discussion paper. There-fore, the original hypothesis is reformulated to account for the fact that hybrid texts are not only the product of a translation process but that they can also be produced as original texts in a specific cultural space, which is often in itself an intersection of different cultures.