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Petroleum-based fuels are used extensively as a result of the rising energy demands. Studies on fuels that will replace these fuels are now ongoing. In this study, performance, emission values of 4 different fuels at 4 different torque values were evaluated, and energy and exergy analyses were done utilizing combinations of gasoline, natural gas, and methanol. The tests employed a Lombardini LGW 523 2-cylinder 4-stroke engine. Four different fuels (gasoline, gasoline plus 50 g of natural gas, M20, and M20 plus 50 g of natural gas) were tested at a constant 3000 rpm with four different torque values (5, 10, 15, 20). In tests, it produced the lowest specific fuel consumption and the best emissions when combined with 50 g of natural gas fuel. The purpose of this study was to show that as torque increased, values for fuel, network, exhaust, absorption water, and energy destruction increased, while rates of lost energy decreased and rates of energy destruction increased.

No mundo atual em que vivemos, em constante mudança, o setor dos transportes tem um papel crucial na atividade económica mundial. Contudo, representa um consumo elevado de recursos energéticos e ainda é um dos principais responsáveis pela emissão de gases com efeito de estufa. A mobilidade elétrica e eletrificação das frotas contribuiu para uma redução direta da emissão de gases, representando uma vantagem sobre os veículos com motores de combustão interna. Todavia, a limitação dos sistemas de armazenamento de energia elétrica em termos de autonomia (número de quilómetros percorridos) ainda é um dos maiores entraves a uma maior penetração no mercado dos veículos elétricos. No setor mais específico dos autocarros elétricos, em particular o autocarro de aeroporto, esta desvantagem é amplificada não só pela dimensão e peso, mas também pelos sistemas auxiliares de aquecimento, ventilação e ar-condicionado (AVAC) inerentes a este tipo de veículos. O presente trabalho tem por objetivo a análise e otimização da eficiência energética do modelo e.Cobus, um autocarro de aeroporto. Para alcançar o objetivo foram estudadas algumas unidades e.Cobus em condições reais de operação e analisadas as potências e consumos de energia das diferentes cargas, criando diversos dataset’s. Com os dataset’s elaborados, e recorrendo à plataforma de aprendizagem máquina WEKA, e aplicação de alguns algoritmos, foram desenvolvidos modelos de previsão do consumo de energia que permitiram otimizar a capacidade de armazenamento energético (baterias) destes autocarros, em função da utilização e local geográfico

Engineered cementitious composites (ECCs) are special types of fibre-reinforced cementitious composites (FRCC) with higher strain capacity which can be achieved with low fibre volume as low as 2% and total elimination of coarse aggregates. Due to the outstanding performance of ECCs, they are suitable for various construction and repair applications. However, in order for ECCs to achieve their properties; a high amount of binder which is primarily composed of Portland cement (PC) is used alongside a special type of ultrafine silica sand (USS) which is different from the conventional natural fine aggregates. The production of PC is known to be detrimental to the environment due to its high carbon dioxide emissions coupled with the high consumption of natural resources. Thus, the high use of PC content in ECCs posed a sustainability threat. Similarly, the USS used in ECCs are not readily available everywhere and are expensive. The processing of the USS coupled with its transportation over long distances would also increase the cost and embodied carbon of ECCs. Hence, in order to promote more development and applications of ECCs for various applications; this dissertation aims to provide innovative ways to improve the sustainability of ECCs and their performances. This dissertation offers four solutions to improve the sustainability of ECCs which are (i) use of unconventional industrial by-products as partial replacement of PC (ii) total replacement of PC in ECCs with alternative sustainable binders (iii) replacement of USS in ECCs with recycled materials and (iv) the use of supplementary cementitious materials to replace a high volume of PC. The findings from this study revealed sustainable ECCs with acceptable mechanical and durability performance can be achieved with the use of alternative binders or replacement of the conventional USS used in ECC mixtures. The sustainability and cost assessment of the ECCs indicated that the incorporation of industrial by-products such as blast furnace slag (BFS) especially at higher content is beneficial to reducing the negative environmental impact and economic burden associated with ECCs compared to the conventional ECC. The sustainability index and cost index of the ECCs further showed that the use of BFS is more beneficial when the sustainability and cost of the ECCs are compared with the corresponding performance. Similarly, the use of recycled materials as an alternative to USS was found to result in a significant reduction in the embodied carbon and cost of ECCs. The use of recycled materials such as expanded glass (EG) as aggregates in ECCs was also found to improve the thermal insulation properties of ECCs making such ECC suitable for the production of building envelope elements.

SUMMARY A NEW METHOD FOR THE ORIENTATION AND DESIGN OF A BUILDING OF MINIMAL ENERGY CONSUMPTION Substitution of passive solar systems for the `dirty` combustion of fossil fuels for energy use in buildings to keep the environment biologically clean, can make important contributions to the health, both of individuals and of the global ecosystem, as well as contributing to the energy economy. Local outdoor chemical pollution, with all the damage it causes, can also be reduced with energy-cone ious design. A new method for design and orientation of an energy conservative building is presented for the use of architectural, urban planning, and energy engineering purposes. The precedure of the thesis is explained in five chapters. The concept of the energy conservative building is given in passive systems' methodology in Chapter 1. Also in the same chapter, the climatological effects on the building envelope and a review of current calculation procedures and computer programs with solar heating and cooling system capabilities are included. Successful passive solar architecture integrates energy conservation with passive solar heating, natural cooling and day lighting. The result can be a comfortable and economic building that uses 50%-90% less operating energy than most contemporary buildings. A world wide interest in passive solar architecture has developed since last five years because it provides an alternative to the trend toward an overdependence on lighting, heating, ventilating, and air conditioning equipment to maintain a livable and productive indoor environment in modern building. Building practitioners in many devoloping countries are interested in passive solar methods which may be integrated into the building design using familiar and readily available materials. Passive solar architecture has emphasized heating of residences in temperate climates; however, passive strategies have now spread to nearly all building types and most climates. The process is more complex for institutional and commercial buildings than for residential, but the same concepts always apply. viiiHour-by-hour simulation provides the backbone for design analysis. For smaller or simpler buildings simplified methods are usually based on monthly analysis. For larger or more complex buildings, the trend is to take full advantage of the inceased computing power of the current generation of powerful microcomputers in order to use simulation directly for design. Convenient design tools based on simulation are becoming available. The entire area of design tools appropriate to passive solar architecture needs much additional effort. Rasearch in the software design area, with powerful microcomputers, expert systems, and computer aided design techniques, promises to aid greatly in the spread of passive solar strategies. The second chapter is a review of the methods of estimation of hourly beam, diffuse and reflected solar radiation data for vertical and horizontal surfaces; whereas in this chapter Liu-Jordan's equations have a significant emphasis and are explained in full detail. There is evidence with the increasing emphasis on the use of solar energy in buildings, that much of the past solar radiation data will be rehabiliated and additional data will be collected in the future; however, it is unlikely that the hourly data to be taken will be extended to cover surfaces other than the horizontal for the majority of the stations. Liu and Jordan conducted extensive analyses during the early I960' s on the available solar radiation data and developed several emperical correlations that can be used to estimate the available solar radiation on `average` days for each month of the year and for a larger number of locations in the United States and Canada. Using the correlations, it is possible to take the monthly average daily total radiation on a horizontal surface, divide the daily total into direct and diffuse components, convert each component into hourly values, and then compute the hourly value of either component on a surface of any orientation desired. In the third chapter shadow analysis techniques for window and building energy studies are examined in detail. These techniques are examined under two parallel groups of classification. In the first group, roughly, the methods deal either with the building as a whole or only with the windows. In the second group, however, the methods are classified according to the first or second position of the observer. ixShading and solar influences on a building can be understood from two different observer positions. At the first position the observer stands at the ground or the building element and looks toward the Sun. The entire yearly movements of the Sun and relationship to the modifying intermediate conditions are seen at one time j thus, from the single station point, the observer has a yearly picture of solar movement. The disadavantage of this technique is that every position of the subject surface must be seperately analysed with a a new drawing and accompanying calculations. For a total analysis, a continious three-dimentional site volume must necessarily be broken into discrete representative points each of which is seperately analysed. Without intermediate obstructions any point on a site is equivalent in a solar analysis, since solar rays are parellel. However when the obstruction is large or close, its influence on different station points may be quite varied, such as on an urban. Since the proximity of the obstruction determines the the degree of variation in complex situations, differences may be considerable. Therefore, the movement or location of shadows is impossible to analyze, for only by accident can one determine whether the discrete object point is at a shadow edge. The crucial issue of total overshadowing effects and shadow patterns cannot be seen, nor can the entire building be examined at one time. In the second position, as used in the new method, the observer is located at a spot between the Sun and the building. By considering both the Sun and the entire building at once, all surfaces in any orientation can be observed under solar illumination. In this position, the relationship of of one portion of the site can be understood acting on another portion of the site. It is clearly seen from the examples that in the methods dealing only with the windows, the observer is, generally, in the first position, whereas in the methods which consider the building as a whole, the observer is in the latter position. The method is explained in details and step by step with a set of examples in Chapter 4. The method is an optimisation of the total percent of the sunlit area and the thermal effect due to the beam component of total solar energy on the vertical exterior surfaces of a building of minimal energy consumption, in Olgyay's bioclimatic chart which considers temperature, solar energy, wind, precipitation, relative humidity and vapor pressure. In other words, the method is a new and comprehensive interpretation of Olgyay's well known Overheated period charts. By replacing the secondposition of the observer in hourly simulation by the original gnomonic diagrams based on the first position of the observer, the metod gets closer to the aims of Olgyays' in the interpretation of architectural principles, site selection, sol-air orientation, solar control, environment and building forms, wind effects and air-flow patterns, and finally the thermal effects of materials. The method assumes that solar radiation does not penetrate the building; therefore it deals neither with the heat transfer problems nor the thermal storage capacity of the building, for the time being. The method does, however, generate relaible kernel data base for future research work on building heat transfer problems. The method is composed of two parts, the second being based on the first. The first part of the method deals with the changes in the sums of the total annual percents of sunlit areas (sunny portion of total exterior walls/total area of exterior walls) of a building at any location, relative to the changes in the orientation. In the second part, the thermal energy of the direct component is added to the variables mentioned above; e.i., location, geometrical design and orientation of the building. Thus, each wall is taken into consideration seperately, with the changes of intensity of solar energy and the percentages of sunlit area on it, due to the changes of the orientation of the building. The method is compiled in ten steps, of which the first five build the primary part, and the last five the secondary. The steps are as follows: 1. Olgyays' bioclimatic chart is adapted to the geographical place. The Overheated and the Underheated periods for selected hours of daytime are marked for selected days. For the selected hours of the selected days 2. percentages of sunlight on the walls of the building of a given orientation are computed, with any shading algorithm of parallel projection. 3. areas of sunlight (mE) on the walls of the building of a given orientation are computed, 4. total percentage of sunlight on the building is computed and grouped under two intensities, e.i. the Overheated and the Underheated. xi5. The annual sums of the total percentages of sunlight for the Overheated and Underheated periods are devided by the number of the Overheated and Underheated daytime hours respectively. 6. Solar thermal energy due to the beam component of hourly radiation is computed for each orientation (KJ/mz.h). 7. Solar thermal energy due to the beam component of hourly radiation is computed for each wall (KJ/h). 8. Total solar thermal energy gain of the building due to the beam component of hourly radiation is computed (KJ/h). 9. Hourly total solar thermal energy gains of the building are grouped under two intensities, the Overheated and the Underheated. 10. The annual sums of total solar thermal energy gains of the building for the Overheated and Underheated groups are devided by the number of Overheated and Underheated daytime hours respectively. application of the first part of the method is done by three blocks of passive apartment houses of the same area and hight, but of different design, for istanbul and Antalya, and for 1., 11., and 21. days of the months. For the second part, however, only the second block is examined for istanbul, and only for 21. days of the months. Hence comparisons of two sets of meteorological data and all the parameters mentioned above may be seen clearly from the graphics relative to the changes in eight orientations, e.i., North, North-East, East, South- East, South, South-West, West, and North-West. A minor modification was made in Olgyay's Overheated period charts in order to eliminate what was believed to be erroneous results by the use of Liu-Jordan equations near the sunrise and sunset hours for the application of the second part of the method. Although percentages of sunlight on the vertical exterior walls are computed with a shading technique based on Conlon's JPCSHAD parallel projection algorithm and the inclusion of the thermal effect mentioned above is done by Liu-Jordan's well known equations, the method is still applicable to other scientists' formulae and shadow analysis models as well. At the last chapter, the method is evaluated and further possible reseach work are pointed out. xiiThe method may be used to generate a wide variety of building blocks. The irradiance load on external surfaces of building blocks of any rectangular design may be evaluated for any orientation, time of day and for different localities. This evidently provides the designer with useful information, guide lines and design aids expanding his ability to manipulate the parameters of form for the control of solar environment and to develop practical indicators and building regulations for planning control. The method may furter be used in a generative process to define alternative proportion of block's sides, configuration of surroundings, street widths, physical characteristics of building surfaces for appropriate solar load criteria. Thus the method may be employed directly in conjunction with other performance criteria for a sythesis of an integrated architectural solution. xiii ÖZET Yapıların, enerji korunumu için yönlendirilmesi ve biçimlendirilmesinde, dış kabuk düşey yüzlerindeki doğrudan güneş ışınımına bağlı, güneşlenme yüzdeleri ve ısıl etkilerin Olgyay konfor bölgelerinde gözlemcinin 2. durumuna göre optimizasyonunun yapıldığı bu metod, iki kademeden meydana gelmektedir: Birinci kademede herhangi bir enlem, boylam ve biçimdeki yapının, düşey dış kabuk elemanları üzerindeki yıllık ortalama toplam güneşlenme yüzdeleri (güneşli alan/toplam alan), güneş ışınımı, bağıl nem, sıcaklık ve hava hareketlerine bağlı Olgyay konfor bölgelerindeki iki şiddet grubu, En Az Sıcak Dönem (EASD) ve En Sıcak Dönem (ESD) altında toplanmakta ve bu değerlerin yönlendirilişe göre değişimi incelenmektedir. Başka bir deyişle, yer, biçim ve yön değişkenlerinin birbirleri üzerindeki etkileri güneşlenme yüzdelerindeki farklılıklar ile belirlenmektedir. ikinci kademede yukarıdaki değişkenlere doğrudan güneş ışınımının düşey yüzeylerdeki ısıl etkileri de eklenmekte ve yapının bütünü ile ilgili, yer, biçim ve yön değişkenlerinin etkileşimine, beher duvarın konumuna ve üzerindeki saatlik güneşlenme yüzdelerine bağlı enerji kazançlarındaki farklılıkların ortalamaları da katılmaktadır. ikinci kademenin uygulamasında Liu- Jordan denklemleri, dünya sathında denenmiş ve kusurları ortaya çıkmış olduğu için, tercih edilmiş; ancak metod diğer araştırıcıların bağıntılarına da açık bırakılmıştır. Yeni metodun gelişimini hazırlayan konular başlıca üç bölüm içinde incelenmiştir. Birinci bölümde enerji korunumlu yapının tanımı pasif sistem metodolojisi içinde verilmekte; aynı bölümde, yapının dış kabuğunu etkileyen iklim elemanları kısaca ve bilgisayarlı ısıl enerji analiz metodları tarihsel gelişim içinde, ikinci bölümde metodun 2. kademesi için önem taşıyan güneş enerjisi verilerinin elde ediliş yolları incelikleri ile açıklanmaktadır, üçüncü bölümde ise yapılarda uygulanan gölge analizi metodları gözlemcinin durumuna göre tanıtılmaktadır. Dördüncü bölümde metod ve inceliklerinin anlaşılabilmesi için bir dizi uygulama sunulmakta, ayrıca birinci kademenin uygulanmasında yararlanılan JPCSHAD gölge algoritması tanıtılmakta ; sonuç bölümünde ise metod değerlendirilmekte ve ileriye dönük araştırmalar için önerilerde bulunulmaktadır. vii 145

Esta dissertação oferece contribuições para o campo da energia eólica, e fornece um roteiro claro para a tomada de decisão baseada em dados, bem como orientações práticas para otimizar a operação e manutenção. No contexto atual da transformação digital e crescente demanda energética surge a necessidade de soluções inovadores e sustentáveis em larga escala, como a energia eólica offshore. A energia eólica é uma fonte de energia renovável que tem o potencial de contribuir significativamente para a matriz energética global. A implementação e operação de projetos eólicos offshore são desafiadores devido aos custos elevados e à natureza intrínseca dos riscos no ambiente marítimo, por isso necessitam operar em sua máxima eficiência e desempenho, tendo em vista a viabilidade económica. Este trabalho tem como objetivo a compreensão dos fatores principais que influenciam o desempenho energético dos aerogeradores através dos dados que revelam as interrupções e falhas de sistemas. Os resultados obtidos nesta pesquisa destacam a necessidade de uma abordagem integrada, buscando o conhecimento técnico especializado com a aplicação de tecnologias de monitoramento em tempo real e análise de dados. Ao reconhecer os padrões de falhas e as lacunas de eficiência, os gestores podem direcionar seus esforços para aprimorar a fiabilidade, a disponibilidade e a performance geral dessas unidades geradoras de energia elétrica. Através da implementação das recomendações resultantes deste estudo, espera-se que as instituições possam alcançar uma expressiva rentabilidade e sustentabilidade, alinhando-se de forma eficaz com as demandas atuais, garantindo uma posição sólida no ambiente empresarial e contribuindo para um futuro energético mais equilibrado.

THE EFFECT OF ADDITIVES ON THE FUSION TEMPERATURES OF COALS SUMMARY In coal processing, coal ash may cause serious problems such as clinker trouble in fluidized bed gasifiers, sintering in stoker combustors, agglomeration in fluidized bed combustors, fouling of heating surface in combustors, vaporization of harmful elements from the ash. Therefore, prediction of ash behavior is of vital importance, particularly for combustion systems In fluidized bed combustion systems, agglomeration (sintering) of ash (coal) and bed material particles can cause severe problems. As a result of agglomeration, deposition can form on heat transfer surfaces and bed walls. Accumulation of sticky ashes on surfaces can cause substantial decrease in heat transfer coefficient, disturb air distribution and consequently fluidization in the bed. In the most serious cases, sintering of particles can lead to heavy agglomerate mass which finally disturb fluidization and combustion completely. In these cases the system has to be dismantled in order to remove agglomerates and restore the normal operation. The measurement of so called characteristic ash temperatures, namely initial deformation temperature (IT), softening temperature (ST), hemispherical temperature (HT) and fusion temperature (FT) is considered to be one of the best methods to estimate the behavior of coal ash in coal combustors in practice. The agglomeration is a process which describes formation of agglomerates from particles under heating. The earlier works suggest that, in fluidized bed combustors, agglomeration can occur as a result of partial melting and stickiness of bed particles due to the operating of fluidized bed at temperatures higher than the melting point of coal. But later research indicate that agglomeration can occur at temperatures much lower than the ash fusion temperature. The temperature at which agglomeration starts is called first sintering temperature. The properties and behavior of ashes are remarkably different among coals and since coal ash is extremely complex mixture of minerals it is not possible to predict the fusion behavior of such mixture from its chemical composition with a reasonable accuracy. Many correlations have been developed to estimate the softening and fusion behavior of ashes from their chemical composition, in general, all of them suggest that the softening and fusion temperatutes increase as the amounts of asidic oxides (SİO2, AI2O3) in the ash increase. Therefore, it is essential to study the individual coal deposit in order to see how they exactly behave in practical combustion. The objectives of this work is to determine the characteristic ash temperatures of some major Turkish lignites, to investigate the relationship between their temperatures and inorganic compositions and relationship between ash fusiontemperatures and inorganic compositions and relationship between ash fusion temperature and agglomeration temperature of some selected coals. The effect of addition of some metal oxides which are the major component of ashes of coals on the characteristic temperatures is also investigated. Ten coal samples studied were taken from the major lignite deposits in various districts of Turkey. One sample out of ten is oil shale. The samples are ; 1 ) Beypazarı - Ankara 2 ) Çan - Çanakkale 3 ) Elmalı ( Soma ) - Manisa 4 ) Eynez - Manisa 5 ) Deniş ( Soma ) - Manisa 6 ) Göynük - Bolu 7 ) Göynük Oil shale - Bolu 8 ) Kısrakdere - Manisa 9 ) Tunçbilek - Kütahya 10) Yatağan - Muğla The following analyses were carried out in order to characterize coal samples and ashes : Proximate analysis, elemental analysis, measurement of characteristic temperatures and chemical analysis of ashes. Coal samples were crushed and sieved to - 200 mesh and ashes were prepared using the TS 330 procedures. Ash compositions were determined according to ASTM procedure D 2795 - 86. Ash fusion measurements were made by using a LECO AF - 500 type ash fusion furnace with digital read - out, sensivity of 5K and a maximum temperature of 1844 K according to the ASTM procedure D 1857 - 68. Ash cones were prepared and put into the furnace and were heated to the fusion temperature with a heating rate of 8 K/ min. under oxidizing gas atmosphere. The results are presented as the an average values of repeated measurements. The results of chemical analysis of ashes and ash fusion measurements are presented in Table 1 and Table 2 respectively. As seen from Table 2, initial deformation temperatures and fusion temperatures of lignites change between 1377 - 1573 K and 1482 - 1844 K, respectively. The fusion temperature of Eynez lignite was out of the temperature range of ash fusion furnace and it could not be measured exactly. Comparison of Table 1 and Table 2 indicated that, in general, coals with higher Si02 and lower Fe203 contents such as Eynez, Elmalı, Kısrakdere, Tunçbilek and Yatağan lignites have higher initial deformation and fusion temperatures while coals with higher Na20 percentages have lower fusion temperatures. However, no regular relationship is seen between chemical composition and critical temperatures of ashes. For example, in spite of their high Na20 percentages, Eynez, Kısrakdere and Tunçbilek lignites have fusion temperatures higher than that those with lower Na20 percentages. In Figure 1, the initial deformation temperatures are given as a function of total percentage of (Na20 + K20 + CaO + MgO). These oxides are called basic oxides which are considered, chemically, to be the most active components and have the leading role in agglomeration (sintering) behavior of ash. It is clear from figure that no regular relationship between composition and deformation temperature can bedescibed for original coal ashes. The initial deformation temperature differs widely even for ashes having nearly the same total basic oxide percentage. A set of experiments was carried out by using of Na2C03, K2CO3, CaO and MgO as additives to ashes in order to investigate the relationship between the X U.m&<*J..lIX-/.CA,I1^-TVJX^VS^IT : Initial deformation temperature, ST : Softening temperature, HT temperature, FT :Fusion temperature. Hemispherical composition and fusion charteristics for the individual ashes. In these experiments, CaO and Na20 contents of all ashes were increased by adding of CaO and Na2C03. K2C03 and MgO were added only to Beypazarı lignite ash. The characteristic temperatures of Beypazarı Elmah, Eynez, Tunçbilek and Yatağan lignites and Göynük oil shale decreased regularly with increasing CaO content while no considerable changes was observed for other lignites. A maximum decrease of 130 K was determined in fusion temperature with an increase of 9% in CaO for Eynez and Yatağan lignites. The Na20 content of ashes was increasd by using Na2CÛ3. Increasing of the amount of Na20 lowered the characteristic temperatures of Beypazarı, Çan, Eynez, Kısrakdere, Tunçbilek and Yatağan lignite ashes. Temperature profiles of Elmah XIlignite ash had a minimun around 8% Na20 below which temperatures decreased while above which increased slightly with increase in Na20 contest. Increasing of Na20 content by 10%, caused a 120 K and 180 K reduction in fusion temperatures of Beypazarı and Eynez lignite, respectively, which were the highest reductions determined. Other ashes were not affected significantly by the Na20. 10 15 20 25 30 %{CaO+ MgO+ Na20+ K20} 35 40 Figure 1. Change of fusion temperature of oginal coal ashes with (Na20 + K20 + CaO + MgO) % Another topic studied in this work is the relationship between the agglomeration and characteristic temperatures of lignites. For this purpose, a set of experiments was performed in which the agglomeration temperatures (Tag) of Beypazarı, Çan, Eynez, Kisrakdere, Göynük and Yatağan lignites were determined in a 10 cm id fluidized bed combustor. Results of agglomeration measurements are compiled in Table 3. The difference between agglomeration temperature and characteristic temperatures are also included in the Table. The differences described as AT, = IT - Tag, AT2 = ST - TAG, AT3= HT - TAG, AT4 = FT - TAG Agglomeration tempertures listed in Table 3 are lowest temperatures where first agglomerates formed. Data in the table indicate that agglomeration of lignite can occur at temperatures several hundred degrees below fusion temperature for a lignite in a fluidized bed coal combustor. Values of ATi, AT2, AT3 > AT4 show that the agglomeration behavior of lignites with different ash compositions vary widely and can not be explained on the basis of ash fusion temperature. XIITable 3. Agglomeration Temperature of Some Lignites. X1U ÖZET Kömür yakma sistemlerinde karşılaşılan sinterlesme ve aglomerasyon olayları, yanmanın sürekliliği açısından problem yaratmakta ve sistemin verimim olumsuz yönde etkilemektedir. Aglomerasyon, kül taneciklerinin birbirine yapışıp, katı bir kütle haline gelmesi olayıdır ve özellikle akışkan yataklı yakma sistemlerinde karşılaşılan önemli bir. problemdir. Temel olarak kömürün anorganik yapı özelliklerinden kaynaklanmaktadır. Bu nedenle JmL ergime sıcakhldarı ve aglomerasyon özellikleri arasında bir etkileşim olduğu sarınmaktadır. Bu çalışmada, 9 linyit ile bir bitümlü şistin küllerinin anorganik yapılan ile özgül sıcaklıkları olarak bilinen, başlangıç deformasyon (İT), yumuşama (ST), yan küreselleşme (HT) ve akma {FT) sıcaklıkları arasındaki ilişki incelenmiştir. Çalışmada, hem orjinal, hem de belirli oranlarda, Na2C03, K2C03, CaO ve MgO katılarak bileşimleri değiştirilmiş olan `katkılı küller` göz önüne alınmıştır. Küllerin anorganik yapılan, standart yöntemler kullanılarak belirlenmiştir. Özgül sıcaklıkları LECO AF 500 model bir cihaz kullanılarak, ASTM D 1857 ' ye göre oksitleyici atmosferde ölçülmüştür. Aglomerasyon sıcaklıkları ise 10 cm çapında bir akışkan yatakta ölçülmüştür. Orjinal küllerin İT değerleri 1377-1576 K, ST değerleri 1414-1801 K, HT değerleri 1460-1814 K, FT değerleri 1482- 1844 K arasında değişmektedir. Özgül sıcaklıkları en yüksek olan kömü Eynez linyiti, en düşük olan ise Göynük bitümlü şisti olmuştur. Orjinal küllerin anorganik yapılan ile özgül sıcaklıklan arasında sistematik herhangibir ilişki görülmemiştir. Genel olarak, Na20 içerikleri yüksek olan kömürlerin çoğunlukla daha düşük sıcaklıklarda, buna karşın SİO2 oranlan yüksek ve Fe203 oranlan düşük kömürler ise daha yüksek sıcaklıklarda ergimiştir. Ancak bu durum incelene bütün kömürler için, geçerli değildir. Aynı tür küllerin yapısal değişimlerini özgül sıcaklıklara etkisini görmek amacıyla, bazı küllere değişik oranlarda Na2C03, K2CO3, CaO ve MgO katılarak hazırlanan katkılı küllerle yapılan ölçümlerin sonuçlan, sıcaklıklan en fazla etkileyen katkının Na2C030İduğunu göstermiştir. Toplam Na20 içeriğine bağlı olarak, özgül sıcaklıklarda genelde bir düşme eğilimi gözlenmiştir. Na20 katkısı bazı kömürlerin ergime sıcaklıklarını 120 K kada^düşürmüştür. Kömürlerin aglomerasyon sıcaklıkları, deformasyon sıcaklıklarına (IT) allında kalmaktadır. Aglomerasyon sıcaklıkları İT değerlerinden 175-346 K, ergime sıcaklıklarından ise, yaklaşık olarak 346-551 K daha düşük olmuştur. Akışkan yataklarda yanan kömür taneciklerinin sıcaklığının ölçülen ortalama yatak sıcaklığından yaklaşık olarak, 100-150 K daha yüksek olduğu göz önüne alındığında, aglomerasyonun deformasyon sıcaklığında veya ona çok yalan sıcaklık seviyelerinde başladığı anlaşılmaktadır. 79

II ABSTRACT Climate change is expected due to the increasing atmospheric concentrations of carbondioxide and other trace gasses, which lead to changes in the radioactive balance of the atmosphere. Such changes propagate further to those in temperature i and other climatic variables. Hydrologic systems and water resources are likely to be seriously impacted by global climate change. Such processes as surface runoff, precipitation, soil moisture, groundwater, water quality, and sea levels will be significantly exposed to effects of climate change. Eventually, these effects will have to be considered in water resources planning and management. The study presented stems from the above needs and addresses the problem of climate change-water resources interactions. It is intended here to investigate the possible effects of climate change on watershed scale hydrologic processes and water demand. Within this context, the current methods used in developed countries are applied to the case of the Gediz River Basin, and possible impacts of changes in climatic variables, i.e., precipitation and temperature, are investigated as they relate to runoff The results of the study should not considered as exact values to represent the effects of climate change. They are essentially `estimates` on `likely` effects of an expected climate change. However, the results also show that, if the prescribed climate change scenarios do occur in the future, they will have significant effects on the hydrology of the basin which, in turn, affects water demand for various water resources development plans. Accordingly, the study presented should be considered as an initial step towards assessment of climate change impacts and should be reaccomplished in future attempts towards any planning or management activity in the basin. ÖZET İklim değişikliği, atmosferdeki karbondioksit (CO2) ve diğer antropojen sera gazı konsantrasyonlarının giderek artması sonucu beklenmektedir. İklim değişikliğinin sonucunda beklenen en önemli olgu, sıcaklık, yağış, evapotranspirasyon, akış gibi temel iklimsel ve hidrolojik değişkenlerdeki muhtemel değişimlerdir. Bu etkilerin su kaynakları planlama ve yönetiminde değerlendirilmesi gerekmektedir. Sunulan çalışma, iklim değişikliğinin su kaynakları ile olan ilişkisini incelemektedir. Bu değişimlerden hidrolojik çevrimin ve su kaynaklarının gerek miktarı ve gerekse kalitesinin de etkilenmesi beklenmektedir. Dolayısıyla, küresel iklim değişikliğinin havza su dengesine ve su kaynaklarının planlama ve yönetimine de yansıması söz konusudur. Bu kapsamda sunulan çalışmada alt havza bazında sıcaklık ve yağış gibi iklim parametrelerinin, akıma olan etkileri incelenmiş ve duyarlılık analizi ile sonuçlar değerlendirilmiştir. 75

Devido à crescente preocupação com as alterações climáticas e à consequente mudança de paradigma, gradualmente são utilizados mais veículos elétricos e híbridos, como é o caso dos FCHEV (Fuel cell Hybrid Electric Vehicle). Como é característico nos veículos híbridos, a existência de duas fontes de energia faz com que seja crucial otimizar a distribuição de potência, sendo esta a chave para melhorar o desempenho do veículo. Assim, definiu-se como medida principal de desempenho o consumo equivalente em Gasoline Gallon Equivalent, que efetua um tradeoff entre o consumo de hidrogénio e o consumo ponderado de energia da bateria, em função do seu estado de carga. Tendo como principais objetivos o aumento do tempo de vida dos componentes e a redução do consumo do veículo, construiu-se uma estratégia de gestão energética em tempo real, baseada em programação dinâmica, com extração de regras de controlo pela response surface methodology e implementação de machine learning para a identificação dos tipos de ciclo de condução. A estratégia foi construída e simulada em Matlab, partindo da modelação do sistema e da implementação da função DPM (Dynamic Programming Matrix), desenvolvida pelo instituto ETH Zurich para efetuar a programação dinâmica. Seguidamente, foi utilizada a função stepwiselm e a app Regression Learner para extrair as regras de controlo e, finalmente, recorreu-se à app Classification Learner para identificar os ciclos de condução. Toda a estratégia foi complementada com o Matlab Coder, para fazer a transição do algoritmo para linguagem C, suportada pela ECU. Os resultados foram analisados no final de cada fase de implementação, validando a metodologia proposta. Assim, na fase de otimização demonstrou-se que é possível melhorar o consumo equivalente, relativamente ao algoritmo implementado no veículo, obtendo-se uma redução média superior a 15%, sem se demonstrarem alterações significativas no consumo de H2. A partir destes resultados, efetuou-se a extração de regras de controlo, utilizando duas estratégias distintas: regressões não lineares e árvores de decisão. No caso da primeira, não foi possível demonstrar que efetivamente o consumo equivalente é menor, apesar da percentagem de redução desse consumo ser em média superior a zero. No caso da segunda, a robustez do modelo de machine learning demonstrou que em média o consumo equivalente é menor do que no algoritmo atualmente presente no autocarro, sendo que a percentagem de redução em média ultrapassa os 10%. Com ambas as estratégias, as alterações no consumo de H2 não se mostraram significativas. Na fase de reconhecimento do ciclo de condução, utilizou-se uma árvore de decisão que foi analisada para diferentes tempos de decisão, demonstrando-se que com 600 e 300 segundos a identificação apresentou os melhores resultados de accuracy, sendo percetível que para 300 segundos será reduzido o espaço em memória na ECU para armazenamento dos parâmetros de condução, mostrando-se também ser mais preciso em cenários mais semelhantes com a realidade. Finalmente os testes de estrada demonstraram melhorias de 15.7% no consumo equivalente, 24.4% no consumo de H2 e 6.8% no rendimento, com a estratégia que utiliza regressões não lineares. No entanto, o algoritmo mais adequado seria o construído com árvores de decisão, que devido à sua complexidade não foi possível de implementar na ECU.

According to the second law of thermodynamics, all human activities cause exergy destructions, adding to additional root causes for carbon dioxide emissions responsibility. It means that current carbon dioxide concentrations are accurately observed, but the root causes and their potential solutions against global warming fall short of achieving the goals of the Paris agreement by almost 45% in terms of decarbonization efforts, as shown in this paper. This result applies to all activities, including the green facility concept. In this respect, the primary aim of this paper is to raise awareness about the essence of the Second Law of Thermodynamics in expanding the green facility concept to reach more effective and sustainable rating methodologies concerning the climate crisis. A new evaluating and rating model with a set of exergy-based green building metrics that relate additional carbon dioxide emissions to irreversible exergy destructions has been developed. Examples about apparently green buildings according to the First Law of Thermodynamics are given by showing that these buildings are not green due to additional carbon dioxide emissions responsibility due to exergy destructions. An airport terminal building case is elaborated. It has been shown that although part of the electricity comes from a third-party wind energy provider, it ends up with carbon dioxide emissions responsibility because it is not entirely used in exergy-rational demand points and compares less favorably with an on-site cogeneration system using natural gas by about 30% more emissions responsibility. The results and derivations of new metrics are discussed, which shed light on adding new criteria to existing green building certification programs.