Lentsoane uses the title of his narrative to highlight the theme. Special attention is paid to this. The suspense is captured in the clash between the traditional attitude to life held by the Bapedi and the modem philosophy of life held by the younger generation. Lentsoane effectively uses the concept of a journey to convey his message to his reader. The visit of the antagonist Kgoteledi to the homeland is especially important in this regard, as her family there is conservative and thus strongly supports her actions. But it is also here that she becomes aware of change. Other important techniques used by Lentsoane are: contrast, symbolism, shifting of focus, mirrorimages, naming, summary and retardation, foreshadowing, but also the reference to related matters. This latter technique has an important emphasising function. Although conflict is emphasised all the time, the climax is reached with the announcement that Mihloti, Dikgoneng's girlfriend, is pregnant. The mother (and therefore also the rest of the family) hereby accept that change has also become part of their lives. Kgoteledi comes to terms with the situation and passes away. AFRIKAANS : In hierdie verhandeling word Lentsoane se novelle, Megokgo ya Lethabo, as 'n liefdesverhaal besktyf waarin die liefdesverhouding tussen die minnaars nie deur die jongman se familie goedgekeur word nie, omdat die jong meisie lid van 'n ander etniese groep is. Die beskrywings model wat vir die ondersoek gevolg word, is 'n aangepaste narratologiese model. Boonop word slegs twee van die struktuurlae ondersoek, nl. die inhouds- en die samestellingslae. In die beskrywing van die inhoudslaag is die vier epiese elemente, karakter, handeling, tyd en plek, noukeurig nagegaan, en t.o.v. die onderwerp wat die outeur gekies het, beskryf. Die onderwerp bepaal die onderlinge verhouding tussen die verskillende karakters, en verdeel die handeling in drie groot aksiekategorieë, t.w. die liefdesverhouding, die besware van die jongman se familie, en die uiteindelike troue. Die tydsbegrip word omskryf in terme van 'n tydstip, tydsverloop en tydsomstandighede. Vir die beskrywing van die samestellingslaag van die werk is daar twee kernbegrippe wat uitgelig word, nl. die temabegrip en die tegniek begrip wat 'n verhoudingsbegrip is en nie eenduidig in verwysing is nie. Die tema wat hier vooropgestel word, is die van verandering, en slaan op die voortdurende verandering in die lewe van mense en kulture. Die karakter van die protagonis, Dikgoneng, word in terme van noodsaaklike en bykomende kenmerke beskryf. Die noodsaaklike kenmerke hou met die verhaalsoort of genre verband, terwyl die outeur met die bykomende kenmerke sy Ieser tot vereenselwiging met die protagonis oorhaal. Die antagonis word slegs t.o.v. die noodsaaklike kenmerke beskryf. Lentsoane gebruik die verhaaltitel as 'n belangrike outeursmiddel om die tema van sy werk na vore te bring. Besondere aandag word hieraan afgestaan. Die spanningselement lê opgevang in die botsing tussen die tradisionele lewensopvattings van die Bapedi en die modeme lewensbeskouing van die jong geslag. Lentsoane maak effektief van die reisbegrip gebruik om sy boodskap aan sy leer tuis te bring. Hier is dit veral die antagonis, Kgoteledi, se besoek aan die tuisland, wat belangrik is, omdat haar familie daar behoudende mense is, en haar dus in haar saak sterk steun. Maar dis dan ook hier waar sy van verandering bewus raak. Belangrike ander tegnieke wat Lentsoane gebruik, is kontrastering, simboliek, fokusverskuiwing, spieëlbeeldstelling, naamgewing, tydsversnelling en vertraging, vooruitskouring, maar veral die verwysing na verwante geleenthede wat 'n sterk beklemtoningsfunksie het. Hoewel konflik deurentyd aan die orde is, word die hoogtepunt met die aankondiging bereik dat Mihloti (Dikgoneng se nooi) swanger is. Die moeder (en daarom ook die res van die familie) aanvaar hiermee dat verandering ook deel van hulle lewens geword het. Kgoteledi berus haar hierin en sterwe. / Dissertation (MA)--University of Pretoria, 1999. / African Languages / unrestricted

Purpose:  The purpose is to investigate the use of concrete as a frame material and its effects on carbon dioxide emissions and energy use. Carbon dioxide emissions and energy use are examined from the production stage to the management stage 100 years in the future. In addition, investigate other material compositions in concrete to study the possibilities 0f lower carbon dioxide impact and energy use. Method: The methods used have included investigating one construction project involving two multi-family houses with the same conditions. The investigation conducted is primarily made through calculations of CO2 emission and energy use. Furthermore, a literary study has also been conducted focused on investigating what the impact concrete has on the environment and what different alternatives are available to reduce potential carbon dioxide emissions and energy use in house construction with a concrete frame. The study has focused on both the production phase and the management phase. The construction stage has been investigated primarily within the concrete production, enforcement and including transports. Whereas the management stage has been studied upon the energy use of the buildings and its effect on carbon dioxide emission.  The literature study deals with methods that can be associated with the case study but will also deal with other presumptive methods. Results: The study of the construction project shows that CO2 emission and energy use primarily comes from cement production within the production stage. Whereas, looking at the whole life cycle studied, the primary contributor to CO2 emissions and energy use over time is the management stage of the buildings. The result also shows that by using renewable steel as reinforcement can significantly effect the energy use, as well as, CO2 emission of the production phase. Conclusions: The cement production is one of the biggest causes of CO2 emissions and energy use in the production phase of the studied life cycle. While the management phase is the largest in terms of the total life cycle studied. Several methods are possible to decrease the use of energy use and CO2-emission in the production stage, and to combine those methods is an alternative that suggested

There is an ongoing transition to a more sustainable industry with lower climate impact. As part of this transition, the steel industry is expected to move from the conventional process for producing iron and steel using Blast Furnace (BF) and Basic Oxygen Furnace (BOF) processes, consuming large amounts of fossil fuels. In Sweden, transition to an alternative process route using Hydrogen Direct Reduction of Iron (H DRI) combined with electric arc furnace s (EAFs) is underway. Large H DRI based steel industries are being established and are expected to produce significant volumes of residues. According to the principles of circular economy, these residues should be valorised as products or raw materials to as large an extent as possible. Industrial Symbiosis is a method for increasing industrial circularity by promoting transactions of information and residues to- provide economic and environmental synergies in a network of industry actors. There are existing industrial networks for valorising residues from the traditional iron and steel industry. Notably, large amounts of BF slags are used as a Supplementary Cementitious Material (SCMs) or raw material in cement production. However, there is a lack of research into how these existing networks can manage the residues produced in the new H DRI and EAF based process. There is also a need to better understand to what extent EAF slags can replace BF and BOF slags in valuable applications such as SCM or cement production. Research into these issues is complicated by the fact that no commercially operating HDRI based steel industries exist at present. Therefore, an exploratory and qualitative research approach was chosen to investigate the knowledge and current conditions in a region where such an industry is being established. A case study was conducted to investigate the industrial network surrounding an emerging steel industry that will use H DRI and EAF processes. A theoretical framework was constructed to assess conditions for the development of an Industrial Symbiosis Network (ISN) in such an industry. Social as well as technological conditions important for ISN development were identified.  The growing network of recyclers, metal industries and other actors surrounding the planned steel plant of H2 Green Steel (H2GS) in Boden was chosen as case. Potential ISN participants were identified and participated in four focus group workshops and ten in depth interviews. An overview of expected residues from H2GS was compiled, together with a list of potential methods for valorisation. The Technology Readiness Levels (TRL) of these valorisation processes were assessed, and the social conditions for ISN development were investigated. There seems to be an existing ISN kernel already forming among recyclers and waste management actors surrounding H2GS. Social networks and an exchange of experiences are in place, and technological and economic barriers are perceived as the main obstacles to efficient residue management. The presence of traditional iron and steel industries in the region seems to be a clear benefit to ISN development. Most of the residues originating in the planned H2GS plant are well known and similar to those produced by other steelmakers, except for the large volumes. However, valorisation of EAF slags is a significant challenge. The most mature technology valorising EAF slags as rocky materials in construction seems unlikely to be able to valorise large volumes of EAF slags in the long run. EAF slags has potential as an SCM material or as raw material for cement production. However, these applications require further refining using technologies that are not yet mature. When the development trajectory of these immature technologies can be predicted, the ISN participants can adjust and prepare for the opp ortunities they create. Some valorisation technologies would bring great ISN advantages by improving diversity of inputs and outputs. However, when development trajectories are unpredictable, ISN development is blocked. / Det pågår en omställning till en mer hållbar industri med lägre klimatavtryck. Som en del i denna omställning förväntas stålindustrin röra sig i väg från den konventionella framställningsprocessen för järn och stål som använder masugn och syrgaskonverter där stora mängder fossila bränslen förbrukas. I Sverige pågår en omställning till en alternativ processväg där direktreduktion med vätgas används tillsammans med ljusbågsugnar. Stora industrier baserade på direktreduktion med vätgas håller på att etablera sig och förväntas producera stora mängder restprodukter. Enligt principerna för cirkulär ekonomi bör dessa restprodukter användas som produkter eller råmaterial för andra processer i så stor utsträckning som möjligt. Industriell symbios är en metod för att förbättra industrins cirkularitet genom att främja utbyten av information och restprodukter som kan skapa ekonomiska och miljömässiga fördelar i ett industrinätverk. Det finns existerande industrinätverk för att använda restprodukter från den traditionella järn- och stålindustrin. Särskilt relevant är att stora mängder masugnsslagg används som alternativa cementmaterial eller som insatsvara i cementproduktion. Det finns dock en brist på forskning om hur sådana nätverk kan hantera restprodukterna från den nya processkedjan med vätgasreduktion och ljusbågsugn. Vidare finns ett behov av att förstå i vilken utsträckning ljusbågsugnsslagg kan ersätta masugnsslagg och konverterslagg i tillämpningar som cementproduktion eller produktion av alternativa cementmaterial. Forskning om dessa ämnen försvåras av att det ännu inte finns någon aktiv stålindustri i storskalig kommersiell drift som använder sig av vätgasreduktion och ljusbågsugnsprocesserna. Därför valdes en utforskande och kvalitativ forskningsdesign för att undersöka kunskapen och de nuvarande förutsättningarna i en region där en sådan industri håller på att etableras. En fallstudie genomfördes för att undersöka industrinätverket kring en framväxande stålindustri som kommer att använda vätgasreduktion och ljusbågsugn. Ett teoretiskt ramverk konstruerades för att bättre bedöma förutsättningarna för industriella symbiosnätverk att växa fram i en sådan industri. Sociala så väl som tekniska omständigheter som påverkar nätverkets framväxt identifierades. Det framväxande nätverket av återvinnare, metallindustrier och andra aktörer runt H2 Green Steels planerade stålverk i Boden valdes som fallstudie. Potentiella nätverksdeltagare identifierades och deltog i fyra fokusgruppworkshops samt tio djupintervjuer. En sammanställning av förväntade restmaterial från H2GS sammanställdes tillsammans med en lista över möjliga metoder för att nyttja dessa. Den tekniska färdighetsnivån (TRL-nivån) hos dessa nyttjandealternativ bedömdes och de sociala förutsättningarna för ett industriellt nätverk att växa fram undersöktes. Ett frö till symbiosnätverk verkar redan formas bland återvinnare och restmaterialhanterare runt H2GS. Sociala nätverk och utbyten av erfarenheter finns, och tekniska och ekonomiska barriärer ses som de största hindren för effektiv restmaterialhantering. Närvaron av traditionella järn- och stålindustrier verkar vara en tydlig fördel för framväxten av ett symbiosnätverk. De flesta av restprodukterna som förväntas från den planerade H2GS anläggningen är väl kända och lika de som produceras av andra stålverk, förutom att de kommer produceras i större volymer. Nyttjande av ljusbågsugnsslagg är dock en betydande utmaning Den mest mogna nyttjandemetoden för denna slagg är att använda den som ett stenmaterial i byggnadstillämpningar. Det verkar dock osannolikt att denna metod skulle kunna hitta avsättning för de stora mängderna ljusbågsslagg som väntas på lång sikt. Ljusbågsugnsslagg har potential som ett alternativt cementmaterial eller som insatsvara i cementproduktion. Dessa tillämpningar kräver dock vidare förädling av slaggen med hjälp av tekniker som inte är mogna ännu. När utvecklingsbanan för dessa tekniker kan förutsägas kan nätverksdeltagarna anpassa sig och förbereda för de möjligheter de skapar. Vissa nyttjandemetoder skulle ge stora symbiosfördelar till nätverket genom att öka mångfalden av insatsvaror och produkter som är möjliga. När utvecklingsbanorna inte går att förutsäga blockeras dock symbiosnätverkets utveckling.

Global cement production is continuously increasing from 1990 till 2050 and growing particularly rapidly in developing countries, where it represents a crucial element for infrastructure development and industrialisation. Every tonne of ordinary Portland cement (OPC) produced releases, on average, about 800 kg of CO2 into the atmosphere, or, in total, the overall production of cement represents roughly 7% of all man-made carbon emissions. The present paper aims to deepen the re-use of agricultural solid waste materials as partial replacement of OPC, which can positively contribute to the sustainability of the concrete industry because of their availability and environmental friendliness. In particular, rice-husk ash (RHA) and oat-husk ash (OHA), burned under the right conditions, can have a high reactive silica content, representing very potential pozzolans. The mechanical and physical characteristics of both materials are investigated to evaluate the influence on concrete properties. Subsequently, using the environmental product declarations (EPDs) of the material used, a comparative environmental impact analysis between RHA concrete and ordinary concrete having the same resistance class, is presented. It is concluded that the use of RHA as supplementary cementitious material can serve a viable and sustainable partial replacement to OPC for the reduction of CO2 emissions and global warming potential. / Den globala cementproduktionen ökar från 1990 till 2050 och växer särskilt snabbt i utvecklingsländer, där den utgör en viktig del för infrastrukturutveckling och industrialisering. Varje ton vanligt portlandcement (OPC) släpper i genomsnitt ut cirka 800 kg koldioxid i atmosfären, och, totalt, representerar den totala cementproduktionen ungefär 7% av alla koldioxidutsläpp från mänsklig verksamhet. Det här examensarbetet syftar till att fördjupa kunskapen om och därmed i förlängningen återanvändningen av fasta avfallsmaterial från jordbruket som delvis ersättning av OPC, vilket kan bidra till hållbarheten i betongindustrin på grund av deras tillgänglighet och miljövänlighet. I synnerhet kan risskalaska (RHA) och havreskalaska (OHA), som bränns under rätt process, ha en hög reaktiv kiseldioxidhalt, vilket representerar mycket potentiella puzzolaner. De mekaniska och fysiska egenskaperna hos båda materialen har undersökts för att utvärdera deras inverkan på betongegenskaper. Därefter presenteras en jämförande miljökonsekvensanalys mellan RHA-betong och OPC-betong med samma motståndsklass med användning av miljövarudeklaration (EPD) för det använda materialet. Man drar slutsatsen att användningen av RHA som alternativt bindemedel (SCM) till OPC kan hjälpa till att minska koldioxidutsläppen och den globala uppvärmningspotentialen.

The prevalence of Protein-Energy Malnutrition (PEM) in South Africa has been welldescribed in previous research studies and yet little is known about the nutritional status of toddlers in the Vosloorus Township. Using the research questions as the conceptual framework for the study, an exploratory descriptive survey was conducted to determine. • What factors give rise to malnutrition in the Vosloorus Township? • Why do toddlers on the PEM Programme fail to achieve their expected target weight? Data was collected by means of structured interviews from a sample of 50 mothers in the Vosloorus Township whose toddlers were on the PEM Programme. The fmdings indicated that the poor socio-economic conditions of the majority of households, especially unemployment, low levels of education and ignorance, contributed towards the development of malnutrition amongst toddlers and their failure to thrive on the PEM Programme. Recommendations to reduce levels of malnutrition and transform existing nutrition programmes were made. / Health Studies / M.A. (Nursing Science)

Made available in DSpace on 2016-01-26T12:51:12Z (GMT). No. of bitstreams: 1 rosicleryagi_dissert.pdf: 414700 bytes, checksum: 16f9a0fd1dd26383f4b843678eec9dd6 (MD5) Previous issue date: 2005-07-14 / Brazilian government policy of public health aims to promote and support breastfeeding; consequently reducing the infant mortality as well as improving the children´s quality of life. The objectives of this study were: a) to observe the diet of premature and full-term babies aged under two years, assessing the breastfeeding indicators of the World Health Organization (WHO): exclusive breastfeeding, predominant breastfeeding, complementary proper foods, continued breastfeeding and milk bottle feeding; b) to compare standardized diets among premature and full-term newborns. Casuistics: Two hundred of mothers of newborns and infants participated the study. They were divided into four groups (50 each): Group I (< 4 months); Group II ( between 6 and <10 months); Group III ( between 12 and < 16 months); Group IV ( between 20 and <24 months). Method: At first the project was approved by the Ethics Committee of Research. Afterwards, before the routinely consulting, the mothers answered a questionnaire based on a methodology standardized by WHO about information of diet during the last 24 hours. Results: The majority of mothers was adult (lesser than 20% of adolescents), able to read and write (97%; IC:93 to 99%), living with a partner (estimative of 79.5%; IC:73 to 85%), minority worked outside (27%; IC:21 to 34%). Average of 70.5% (IC:64 to 77%) of cesarean labor and 50.5% (IC:43 to 57%) of premature labor. The minority performed the first breastfeeding in the labor room (estimative of 18%; IC:13 to 25%). In Group I, the rate of exclusive breastfeeding was 40% (IC:26 to 55%), and predominant breastfeeding 28% (IC:16 to 42%). In Group II, the rate of breastfeeding with complementary proper foods was 46% (IC:32 to 61%). In Group III, the rate of continued breastfeeding up to one year was 30% (IC:18 to 45%); and in Group IV, the rate of continued breastfeeding up to two years was 32% (IC:20 to 47%). The rate of milk bottle feeding for babies under one year was 57% (IC:47 to 67%). Conclusions: The characteristics of the groups of mothers and babies were almost homogeneous, both have been following partially the facilitator routines of breastfeeding. As the age of babies increased, breastfeeding diminished, with the early introduction of liquids and complementary diet. The standardized diet of full-term and premature babies was similar. / O Brasil adota uma política de saúde voltada para a promoção, proteção e apoio ao aleitamento materno, como forma de reduzir a mortalidade infantil e melhorar a qualidade de vida das crianças. Os objetivos deste estudo foram; a) caracterizar a amostra e verificar a alimentação de bebês com idade inferior a dois anos, prematuros e a termo, avaliando os indicadores de aleitamento materno propostos pela Organização Mundial de Saúde (OMS): amamentação exclusiva, amamentação predominante, alimentação complementar oportuna, amamentação continuada e alimentação por mamadeira; b) comparar padrões alimentares entre bebês prematuros e a termo. Casuística: participaram do estudo 200 mães de recém-nascidos e lactentes divididas em quatro grupos de 50 mães; Grupo 1 (<4 meses); Grupo II (entre 6 e <10 meses); Grupo III (entre 12 e <16 meses); Grupo IV (entre 20 e <24 meses). Método; O projeto foi aprovado pelo Comitê de Ética em Pesquisa. Antes da consulta rotineira, as mães responderam a um questionário, fundamentado em metodologia padronizada pela OMS, sobre informações alimentares relativas as últimas 24 horas. Resultados: A maioria das mães encontrava-se na fase adulta (menos de 20% de adolescentes), alfabetizadas (97%; lC:93 a 99%), com parceiros (estimativa de 79,5%; 10:73 a 85%), minoria trabalhava fora (27%; 10:21 a 34%). Estimativa de 70,5% (lC:64 a 77%) de parto cesárea e 50,5% (lC:43 a 57%) de prematuridade. A minoria realizou a primeira mamada na sala de parto (estimativa de 18%; lC:13 a 25%). No Grupo 1 a taxa de aleitamento materno exclusivo foi 40% (lC:26 a 55%) e de aleitamento materno predominante 28% (10:16 a 42%). No Grupo II a taxa de aleitamento materno com alimentação complementar oportuna de 46% (10:32 a 61%). Para o Grupo III, a taxa de aleitamento materno continuado até um ano foi de 30% (10:18 a 45%) e para o Grupo IV a taxa de aleitamento materno continuado até dois anos foi de 32% (10:20 a 47%). Nota de Resumo A taxa de alimentação por mamadeira para menores de um ano foi de 57% (10:47 a 67%). Conclusões: As características dos grupos de mães e crianças foram quase homogêneas; ambos seguiam parcialmente rotinas facilitadoras da amamentação. O aleitamento materno diminui com o aumento da idade, havendo a introdução precoce de líquidos e alimentação complementar. O padrão alimentar dos bebês a termo e prematuros foi semelhante.

O monitoramento da razão Z de duas variáveis através de gráfico de controle tem sido um tema recentemente explorado na literatura. Para analisar mais o assunto, o estudo avalia a eficiência e viabilidade de aplicação dessa ferramenta como suporte na tomada de decisão para gerenciamento de capacidade de mão de obra de retaguarda (doravante mencionado como Backoffice) de serviço de empresa do setor bancário. Tradicionalmente, gráficos de controle tem sido utilizados para monitorar o processo produtivo de manufaturas, mas recentemente tem sido adotado para monitoramento de alguns serviços. Apesar de ainda seguir muitos conceitos pioneiros na manufatura, a atividade do setor de serviços apresenta suas particularidades como, por exemplo, a impossibilidade de gerar estoque. Assim, a necessidade de adequar seus recursos à demanda torna-se essencial, sendo fundamental a gestão de controles e sua urgência para que possa reagir rapidamente em caso de variação de demanda e adequar sua capacidade. Em um cenário de restrição de recursos, planejar é crucial para evitar desperdícios e garantir eficiência. O objetivo deste estudo é apresentar o gráfico de controle como ferramenta para monitorar a razão de duas variáveis aleatórias: a demanda e a mão de obra em Backoffice de serviço em um banco. Nesse trabalho, gráfico de controle de Shewhart tradicional e gráfico de controle de Shewhart com regras suplementares são analisados e os resultados obtidos confirmam a possibilidade de utilização da ferramenta de gráficos de controle para o gerenciamento e adequação de mão de obra para atender a demanda. O monitoramento da razão (demanda/ mão de obra) ajudará o gestor a alocar adequadamente o time (mão de obra) de acordo com a demanda e a capacidade produtiva. Como contribuição, o estudo avalia o comportamento da razão Z = X/Y em situação de alta variabilidade da variável X e baixa variabilidade da variável Y . / The monitoring of the ratio Z of two variables through control chart has been recently explored in the literature. This study analyses the efficiency and viability of this tool as a support to the manager\'s decision in capacity management of a Backoffice service in a business banking service. Traditionally, control charts have been used to monitoring production process in manufacturing companies, but recently it has been adopted in monitoring some classes of services. Although many pioneering definitions developed for manufacturing are still applied in the service activities, the service industry has some particularities as the impossibility to generate stock, for example. Thus, the need to adapt the resources of manpower to attend the demand becomes essential mainly in a current financial global crisis, with resource constraints. The control management is fundamental and urgent to plan a fast reaction to adequate its capacity in case of a large demand variation. Thus, monitoring is crucial to avoid vast and ensure efficiency. The aim of this paper is to present a control chart to monitor the ratio of the two random quantities: the demand and the labor of a Backoffice service in a business banking service. In this paper, traditional Shewhart and Shewhart with supplementary rules control charts are considered and the results confirmed the possibility to apply the control charts to help the management to adequate the manpower in order to attend the demand. The monitoring of the ratio (demand/manpower) will help the manager to allocate adequately the team (the manpower) according to the demand and the production capacity. The contribution of this study is the analysis of the behavior of the ratio Z = X/Y in situation of large variability of the variable X and low variability of the variable Y .

The author of this doctoral thesis Theoretical basis of developing and evaluating worksheets for foreign language teaching with a focus on the Spanish language attempts to describe the current situation regarding the creation of worksheets. He highlights the fact that there is no theoretical basis for their production, and no evaluation of the quality and application of these worksheets in the teaching of Spanish. He also outlines ways how to solve this deficit and potential problems in the process of investigation into this topic. The main aim of this dissertation is to analyse the worksheets as a supplementary teaching material and to describe the whole process of their adoption, adaptation, creation, usage, evaluation, revision and actualization. Although the teachers usually complement their usual textbook with autonomous supplementary materials, the lack of methodology or empirical research on this topic is evident. In theoretical part of this doctoral thesis all available sources will be analysed and the emphasis will be put on comparing rules of the textbooks creation to worksheets creation in order to put together relevant information. The similar principles will be highlighted and also differences will be mentioned. Moreover, methods of creating and evaluating worksheets will be...

The construction industry is the largest consumer of materials in our society. Approximately 40% of all materials used are related to this section of the industry. Equivalent is the impact of the sector’s activities to the environment in terms of non-renewable energy sources (grey energy), gas emissions (mainly CO2), solid waste, etc. With concrete being the most widely used construction material (second only to water in total volumes consumed annually by society) and cement being the essential “glue” in concrete, emphasis should be placed on investigating and enforcing appropriate ways, methodologies and policies, to make cement manufacturing and the construction industry in general a more environmental friendly sector. At the same time, by considering, at one hand the significant amount of research and breakthroughs achieved on structural materials and design, as well as the level of sophistication of the modern European Standards and structural codes, and on the other hand, the increasing cases of premature deterioration of concrete structures, particular emphasis should also be placed on safeguarding the service life of reinforced concrete structures (in addition to tackling their environmental burden). That is why it is very important to introduce the sustainable way of thinking and the concept of industrial ecology on the preliminary design stages of a structure, on the material selection process and on the service life estimation stage, in achieving a robust durable reinforced concrete (RC) structure (for a given service life) with the minimum environmental burden. Thus, the main objective of the present Thesis is to focus on identifying and quantifying a structured framework of the appropriate methodologies in formulating an Integrated Design Process (IDP) for the design of durable and sustainable structures at the minimum environmental and economical cost (without compromising issues of structural safety) and also in identifying and demonstrating ways of industrial ecology for the sustainable development of the cement and construction industry. The present Thesis contributes to the evaluation of the environmental cost of each component of concrete and to provide the best possible mix design configuration (by means of a holistic analytical software tool) in terms of low environmental cost, as well as, to assess this proposed configuration in terms of strength and durability requirements. Overall, it has to be emphasized that through the present Thesis a new indicator is proposed for design purposes: the environmental cost, which can be added to the existing strength, durability and economic cost indicators towards an integrated design optimization of concrete structures. Finally, it is concluded that the incorporation of new Supplementary Cementing Materials (SCM), as biomass ashes and especially Rice Husk Ash (RHA), offers new perspectives for decreasing the environmental cost of constructions. / Η κατασκευαστική βιομηχανία αποτελεί τον μεγαλύτερο καταναλωτή υλικών στην κοινωνία μας. Περίπου το 40% όλων των υλικών που χρησιμοποιούνται σχετίζονται με αυτόν τον τομέα της βιομηχανίας. Αντίστοιχο αντίκτυπο έχουν και οι δραστηριότητες του τομέα στο περιβάλλον σε ότι αφορά τις μη ανανεώσιμες πηγές ενέργειας («γκρίζα» ενέργεια), αέριες εκπομπές (κυρίωςCO2 ), στερεά απόβλητα, κλπ. Δεδομένου ότι το σκυρόδεμα αποτελεί το πιο ευρέως χρησιμοποιούμενο δομικό υλικό (δεύτερο μετά το νερό σε συνολικούς όγκους που καταναλώνονται ετησίως από την κοινωνία) και ότι το τσιμέντο είναι η απαραίτητη «κόλλα» στο σκυρόδεμα, έμφαση πρέπει να δοθεί στη διερεύνηση και επιβολή κατάλληλων τρόπων, μεθοδολογιών και πολιτικών για τη μετατροπή της τσιμεντοβιομηχανίας και της κατασκευαστικής βιομηχανίας σε έναν γενικά περισσότερο περιβαλλοντικά φιλικό τομέα. Ταυτόχρονα, λαμβάνοντας υπόψη από τη μια μεριά τη σημαντική ποσότητα έρευνας και τα επιτεύγματα σχετικά με τα δομικά υλικά και τον σχεδιασμό, και επιπλέον το επίπεδο της επιτήδευσης των σύγχρονων Ευρωπαϊκών Προτύπων και κατασκευαστικών κανονισμών, και από την άλλη μεριά τις αυξανόμενες περιπτώσεις της πρώιμης φθοράς των κατασκευών από σκυρόδεμα, ιδιαίτερη έμφαση θα πρέπει να δοθεί στη διασφάλιση της διάρκειας ζωής των κατασκευών οπλισμένου σκυροδέματος (σε συνδυασμό με την αντιμετώπιση της περιβαλλοντικής τους επιβάρυνσης). Για το λόγο αυτό είναι ιδιαίτερα σημαντική η εισαγωγή του βιώσιμου τρόπου σκέψης και της έννοιας της βιομηχανικής οικολογίας στα προκαταρκτικά στάδια σχεδιασμού μιας κατασκευής, κατά τη διαδικασία επιλογής υλικών και κατά το στάδιο εκτίμησης της διάρκειας ζωής, ώστε να επιτευχθεί μια εύρωστη, ανθεκτική κατασκευή οπλισμένου σκυροδέματος (για δεδομένη διάρκεια ζωής) με την ελάχιστη περιβαλλοντική επιβάρυνση. Συνεπώς, ο κύριος στόχος της παρούσας Διατριβής είναι να επικεντρωθεί στον εντοπισμό και ποσοτικοποίηση ενός δομημένου προτύπου κατάλληλων μεθοδολογιών για τον σχηματισμό μιας Ενοποιημένης Διαδικασίας Σχεδιασμού για τον σχεδιασμό ανθεκτικών και βιώσιμων κατασκευών με το ελάχιστο περιβαλλοντικό και οικονομικό κόστος (χωρίς συμβιβασμούς σε θέματα που άπτονται της κατασκευαστικής ασφάλειας) και επίσης για την αναγνώριση και επίδειξη τρόπων βιομηχανικής οικολογίας για την βιώσιμη ανάπτυξη της βιομηχανίας τσιμέντου και σκυροδέματος. Η παρούσα Διατριβή συνεισφέρει στην αξιολόγηση του περιβαλλοντικού κόστους κάθε συστατικού του σκυροδέματος αλλά και στην παροχή ενός καλύτερου δυνατού σχεδιασμού σύνθεσης σκυροδέματος (μέσω ενός ολιστικού αναλυτικού λογισμικού) υπό όρους χαμηλού περιβαλλοντικού κόστους, καθώς και στο να αξιολογήσει την προτεινόμενη σύνθεση υπό όρους αντοχής και απαιτήσεων ανθεκτικότητας. Συνολικά, πρέπει να τονισθεί ότι στη παρούσα Διατριβή προτείνεται για πρώτη φορά ένας νέος δείκτης για σκοπούς σχεδιασμού: το περιβαλλοντικό κόστος, το οποίο μπορεί να προστεθεί στους υπάρχοντες δείκτες αντοχής, ανθεκτικότητας και οικονομικού κόστους προς μια ολοκληρωμένη αριστοποίηση σχεδιασμού κατασκευών από σκυρόδεμα. Τέλος, προκύπτει το συμπέρασμα ότι η ενσωμάτωση νέων συμπληρωματικών υδραυλικών υλικών (SCM: Supplementary Cementing Materials), όπως οι τέφρες βιομάζας και ειδικά η τέφρα φλοιού ρυζιού (RHA: Rice Husk Ash), προσφέρει νέες προοπτικές για τη μείωση του περιβαλλοντικού κόστους σκυροδέματος.

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