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Estudo da ampliação de escala do processo de pré-tratamento alcalino do bagaço de cana-de-açúcar para obtenção de etanol de segunda geração / Scale up study of sugarcane bagasse alkaline pretreatment process for second generation ethanol productionNakanishi, Simone Coelho 05 October 2016 (has links)
No presente trabalho, dados de ampliacao de escala, de um processo de pre-tratamento alcalino em escala laboratorial (2L) para escala piloto (350L) foram avaliados. Os experimentos realizados previamente em escala laboratorial apontaram duas condições potenciais para a ampliacao de escala, a saber: Ensaio 5 (130°C, 30 min, 1,5% m/v NaOH, 0,15% m/m antraquinona) apresentando a maior conversao enzimatica da polpa obtida (64,5%) e Ensaio 7 (170°C, 1,5 % m/v NaOH, 30 min, 0,15% m/m antraquinona) com a maior solubilizacao de lignina (81,0 %). Os experimentos em escala piloto foram realizados nas condicoes apontadas, com e sem a adicao de antraquinona. A reprodutibilidade dos dados em escala piloto foi satisfatoria, considerando o sistema de aquecimento e agitacao mais eficientes do reator piloto em relacao ao reator usado no laboratorio. O uso da antraquinona diminuiu a solubilizacao de carboidratos durante o pretratamento (evitando 67% de solubilizacao quando comparado a reacao sem antraquinona, a 130°C), mas interferiu negativamente na etapa subsequente de hidrolise, principalmente na reacao a 170°C. Dentre as condicoes testadas, o ensaio 5Pil/AQ (130°C, 30 min, 1,5% NaOH e 0,15% m/m antraquinona) foi eleito como a melhor condicao de pre-tratamento, com maior rendimento em carboidratos apos a hidrolise enzimatica, sendo possivel obter (extrapolando os resultados) 290 kg de glicose e 98 kg de xilose a partir de uma tonelada de bagaco (base seca). Para a obtencao de etanol a partir desse hidrolisado, foram realizadas fermentacoes com tres diferentes leveduras - S. cerevisiae CAT-1, S. stipitis NRRL Y-7124 e S. passalidarum NRRL Y-27907. O melhor resultado foi apresentado para fermentacao em batelada alimentada aplicando reciclo de celulas utilizando a levedura S. passalidarum, produzindo 23,3 g/L de etanol (97 % do teorico) com produtividade de 0,90 g/L.h em 24 h de fermentacao no terceiro reciclo. O processo de pre-tratamento alcalino gera, alem da polpa rica em carboidratos, um hidrolisado rico em lignina. A lignina foi precipitada desse hidrolisado apos cada pre-tratamento realizado e caracterizada, apresentando poder calorifico entre 22,8 e 25,3 MJ/kg. / In this study, data scale up for an alkaline pretreatment process from lab to pilot scale was evaluated. Lab scale experiments indicated two potential conditions for the scale-up, namely: 130°C, 30 min, 1.5% w/v NaOH, 0.15% w/w anthraquinone , presenting the highest enzymatic conversion (64.5%); and 170°C, 30 min, 1.5% w/v NaOH, 0.15% w/w anthraquinone with the highest lignin solubilization (81.0 %). The experiments were performed on pilot scale under the aforementioned conditions, with and without anthraquinone. Data reproducibility on pilot scale was satisfactory considering the more efficient heating and stirring reactor system when compared to the reactor in lab scale. Anthraquinone decreases the solubilization of carbohydrates during pretreatment (avoiding 67% solubilization compared to the reaction without anthraquinone, at 130°C), but interferes negatively in the subsequent hydrolysis step, mostely at 170°C. Among the conditions tested, the test performed at 130°C, 30 min, 1.5% w/v NaOH and with 0.15% w/w anthraquinone was chosen as the best pretreatment condition, with the highest carbohydrate conversion after enzymatic hydrolysis, allowing 290 kg of glucose and 98 kg of xylose per a dry base ton of bagasse. In order to produce ethanol from this hydrolyzate, fermentations with three different yeasts were performed - S. cerevisiae CAT-1, S. stipites NRRL Y-7124, S. passalidarum NRRL Y-27907. Fed-batch fermentation with S. passalidarum cell recycling provided the best result, yielding 23.3 g/L ethanol, 97 % (theoretical yield) with 0.90 g/L.h productivity within 24 h of fermentation. The alkaline pretreatment process generates, besides the pulp rich in carbohydrates, a lignin-rich hydrolyzate. Lignin was precipitated from the hydrolyzate obtained after each pretreatment carried out and characterized, presenting heating values between 22.8 and 25.3 MJ/kg.
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Estudo da ampliação de escala do processo de pré-tratamento alcalino do bagaço de cana-de-açúcar para obtenção de etanol de segunda geração / Scale up study of sugarcane bagasse alkaline pretreatment process for second generation ethanol productionSimone Coelho Nakanishi 05 October 2016 (has links)
No presente trabalho, dados de ampliacao de escala, de um processo de pre-tratamento alcalino em escala laboratorial (2L) para escala piloto (350L) foram avaliados. Os experimentos realizados previamente em escala laboratorial apontaram duas condições potenciais para a ampliacao de escala, a saber: Ensaio 5 (130°C, 30 min, 1,5% m/v NaOH, 0,15% m/m antraquinona) apresentando a maior conversao enzimatica da polpa obtida (64,5%) e Ensaio 7 (170°C, 1,5 % m/v NaOH, 30 min, 0,15% m/m antraquinona) com a maior solubilizacao de lignina (81,0 %). Os experimentos em escala piloto foram realizados nas condicoes apontadas, com e sem a adicao de antraquinona. A reprodutibilidade dos dados em escala piloto foi satisfatoria, considerando o sistema de aquecimento e agitacao mais eficientes do reator piloto em relacao ao reator usado no laboratorio. O uso da antraquinona diminuiu a solubilizacao de carboidratos durante o pretratamento (evitando 67% de solubilizacao quando comparado a reacao sem antraquinona, a 130°C), mas interferiu negativamente na etapa subsequente de hidrolise, principalmente na reacao a 170°C. Dentre as condicoes testadas, o ensaio 5Pil/AQ (130°C, 30 min, 1,5% NaOH e 0,15% m/m antraquinona) foi eleito como a melhor condicao de pre-tratamento, com maior rendimento em carboidratos apos a hidrolise enzimatica, sendo possivel obter (extrapolando os resultados) 290 kg de glicose e 98 kg de xilose a partir de uma tonelada de bagaco (base seca). Para a obtencao de etanol a partir desse hidrolisado, foram realizadas fermentacoes com tres diferentes leveduras - S. cerevisiae CAT-1, S. stipitis NRRL Y-7124 e S. passalidarum NRRL Y-27907. O melhor resultado foi apresentado para fermentacao em batelada alimentada aplicando reciclo de celulas utilizando a levedura S. passalidarum, produzindo 23,3 g/L de etanol (97 % do teorico) com produtividade de 0,90 g/L.h em 24 h de fermentacao no terceiro reciclo. O processo de pre-tratamento alcalino gera, alem da polpa rica em carboidratos, um hidrolisado rico em lignina. A lignina foi precipitada desse hidrolisado apos cada pre-tratamento realizado e caracterizada, apresentando poder calorifico entre 22,8 e 25,3 MJ/kg. / In this study, data scale up for an alkaline pretreatment process from lab to pilot scale was evaluated. Lab scale experiments indicated two potential conditions for the scale-up, namely: 130°C, 30 min, 1.5% w/v NaOH, 0.15% w/w anthraquinone , presenting the highest enzymatic conversion (64.5%); and 170°C, 30 min, 1.5% w/v NaOH, 0.15% w/w anthraquinone with the highest lignin solubilization (81.0 %). The experiments were performed on pilot scale under the aforementioned conditions, with and without anthraquinone. Data reproducibility on pilot scale was satisfactory considering the more efficient heating and stirring reactor system when compared to the reactor in lab scale. Anthraquinone decreases the solubilization of carbohydrates during pretreatment (avoiding 67% solubilization compared to the reaction without anthraquinone, at 130°C), but interferes negatively in the subsequent hydrolysis step, mostely at 170°C. Among the conditions tested, the test performed at 130°C, 30 min, 1.5% w/v NaOH and with 0.15% w/w anthraquinone was chosen as the best pretreatment condition, with the highest carbohydrate conversion after enzymatic hydrolysis, allowing 290 kg of glucose and 98 kg of xylose per a dry base ton of bagasse. In order to produce ethanol from this hydrolyzate, fermentations with three different yeasts were performed - S. cerevisiae CAT-1, S. stipites NRRL Y-7124, S. passalidarum NRRL Y-27907. Fed-batch fermentation with S. passalidarum cell recycling provided the best result, yielding 23.3 g/L ethanol, 97 % (theoretical yield) with 0.90 g/L.h productivity within 24 h of fermentation. The alkaline pretreatment process generates, besides the pulp rich in carbohydrates, a lignin-rich hydrolyzate. Lignin was precipitated from the hydrolyzate obtained after each pretreatment carried out and characterized, presenting heating values between 22.8 and 25.3 MJ/kg.
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Identificação e caracterização da primeira exoxilanase da família 11 de hidrolase de glicosídeo a partir do estudo do metatranscriptoma de um consórcio derivado da compostagem / Identification and characterization of the first exo-xylanase from glycosil hydrolase family 11 from the study of the metatranscriptome of a compost-derived consortiaMello, Bruno Luan Soares Paula de 23 August 2017 (has links)
O uso de resíduos agrícolas como fonte de carbono para a geração de energia renovável parece uma solução promissora para reduzir nossa dependência em combustíveis fósseis. Na natureza, como na compostagem, comunidades microbianas formam redes metabólicas complexas que degradam eficientemente a biomassa disponível através de um conjunto de enzimas sinérgicas. Entretanto, a desconstrução da lignocelulose continua uma desafio para a indústria devido a natureza recalcitrante do substrato e a baixa atividade das enzimas, aumentando o preço do biocombustível produzido. Estudos de metagenômica e metatranscriptômica de comunidades microbianas complexas tornam possível acessar as funções metabólicas empregadas por consórcios lignocelulolíticos e revelar novos biocatalisadores que podem melhorar a conversão industrial da lignocelulose. Aqui, através de uma abordagem metagenômica, foi examinada a diversidade de microrganismos obtidos em condições laboratoriais quando um meio definido ou um complexo foi usado no seu crescimento. Em seguida, a comunidade microbiana derivada de compostagem foi crescida em meio mínimo com bagaço de cana-de-açúcar como única fonte de carbono. A degradação do substrato foi monitorada e o metatranscriptoma da cultura resultante foi sequenciado, seguido pela seleção e caracterização funcional de vários alvos. Durante as cinco semanas de estudo, a comunidade microbiana crescida em meio mínimo mostrou maior diversidade e enriquecimento em microrganismos capazes de degradar a lignocelulose do que a comunidade microbiana crescida no meio complexo. A partir do metatranscriptoma foi descoberta a primeira hidrolase de glicosídeo da família 11 com atividade exoxilanase (C21). A estrutura cristalográfica da C21, refinada à 1,76 Å, revelou que a atividade exoxilanase observada se deve a presença de duas alças que não estão presentes nas demais estruturas dos membros da família 11 de hidrolase de glicosídeo depositadas até então. A adição da C21 a um coquetel comercial provocou um aumento na velocidade de hidrólise do Avicel quando na presença de xilooligômeros. As análises metagenômica e metatranscriptômica da comunidade microbiana proveniente da compostagem revelaram que o uso de um meio definido pode deslocar espécies generalistas, levando a uma fonte enriquecida para explorar enzimas com aplicação biotecnológica. Também demonstrou a diversidade de mecanismos envolvidos na degradação in situ da lignocelulose. / Using of the globally abundant crop residues as carbon source for energy generation seems a promising solution to reduce our dependency on fossil fuels. In nature, such as in compost habitats, microbial communities create complex metabolic networks that efficiently degrade the available plant biomass using a set of synergistic enzymes. However, deconstruction of lignocellulose remains a challenge for industry due to recalcitrant nature of the substrate and enzymes low activity, raising the price of the produced biofuel. Metagenomics and metatranscriptomics studies on complex microbial communities can assess the metabolic functions employed by the lignocellulolytic consortia and unveil novel biocatalysts that could improve industrial lignocellulose conversion. Here, using 16S rRNA amplicon metagenomic approach, we examined the diversity of microorganisms obtained in the laboratory setting when a nutrient-limited or nutrient-rich media are used. Then, a microbial community derived from compost was grown in minimal medium with sugarcane bagasse as a sole carbon source. The substrate degradation was monitored and the metatranscriptome from the resulting cultures was sequenced; several target genes were selected and functional characterized. During a five-week time course, the microbial community grown in minimal medium showed greater diversity and enrichment in lignocellulose-degrading microorganisms than the one grown in nutrient rich medium. Metatranscriptomics analysis revealed the first glycoside hydrolase from family 11 with exo-xylanase activity (C21). C21 crystal structure, refined at 1.76 Å, explained the molecular basis of exo-xylanase activity due to two extra loops previously unseen in the other reported structures from members from glycoside hydrolase family 11. A supplementation of commercial enzyme mix with C21 showed improvement in Avicel hydrolysis in the presence of inhibitory xylooligomers. The combination of metagenomic and metatranscriptomic analysis of compost-derived microbial community showed that nutrient-limited medium may displace bacterial generalist species, leading to an enriched source for mining novel enzymes for biotechnology applications. It also unveiled a diversity of mechanisms involved in lignocellulose degradation in situ.
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Dynamic Parenting: Ethnic Identity Construction in the Second-Generation Indian American FamilySinha, Cynthia B 19 November 2010 (has links)
This study explores Indian culture in second-generation Indian American families. For the most part, this generation was not socialized to Indian culture in India, which raises the question, how do parents maintain and teach culture to their third-generation children? To answer this question, I interviewed 18 second-generation Indian American couples who had at least one child. Rather than focus on how assimilated or Americanized the families were, I examine the maintenance of Indian culture. Instead of envisioning culture as a binary between “Indian” and “American,” second-generation parents often experience “Indianness” and “Americanness” as interwoven in ways that were not always easily articulated. I also explore the co-ethnic matrimonial process of my participants to reveal the salience of Indian-American identity in their lives. A common experience among my participants was the tendency of mainstream American non-Indians to question Indian-Americans about India and Indian culture. My participants frequently were called upon to be “cultural ambassadors” to curious non-Indians. Religion served as a primary conduit for teaching Indian culture to third-generation children. Moreover, religion and ethnic identity were often conflated. Mothers and fathers share the responsibility of teaching religion to third-generation children. However, mothers tend to be the cultural keepers of the more visible cultural objects and experiences, such as, food, clothing, and language. Fathers were more likely to contribute to childcare than housework. The fathers in my study believe they father in a different social context than their fathers did. By negotiating Indian and American culture, fathers parent in a way that capitalizes on what they perceive as the “best of both worlds.” Links to the local and transnational community were critical to maintaining ties to other co-ethnics and raising children within the culture. Furthermore, most of the parents in my study said they would prefer that their children eventually marry co-ethnics in order to maintain the link to the Indian-American community. Ultimately, I found that Indian culture endures across first- and second-generation Indian Americans. However, “culture” is not a fixed or monolithic object; families continue to modify traditions to meet their emotional and cultural needs.
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The role of US agricultural and forest activities in global climate change mitigationZhu, En 15 May 2009 (has links)
In 2005 the highest global surface temperature ever was recorded. A virtual consensus exists today among scientists that global warming is underway and that human greenhouse gas (GHG) emissions are a significant cause. Possible mitigation of climate change through reduction of net GHG emissions has become a worldwide concern. Under the United Nation’s Framework convention on Climate Change, the Kyoto Protocol was formed in 1997 and required ratifying countries to co-operate in stabilizing atmospheric GHG concentrations. The protocol took effect on February 16, 2005. The mitigation cost for reducing GHG emissions for the US economy has been argued to be high particularly through the energy sector. Agriculture and Forestry (AF) can provide some low cost strategies to help with this mitigation principally through carbon sequestration but must be competitive with mitigation costs in the rest of the economy. A general equilibrium approach is used herein to evaluate the role of AF mitigation in an economy wide setting. The results show that the AF sectors have significant mitigation potential. Higher carbon prices lead to more sequestration, less emissions, reduced consumer and total welfare, improved environmental indicators and increased producer welfare. AF mitigation increases as the carbon price increase over time. In the earlier periods, while the carbon price is low, AF emissions and sink are quite small compared to the energy sector. As carbon prices increase over time, the AF sectors mitigate about 25% of the net emissions. This verifies McCarl et al's (2001) argument that the AF sectors “may be very important in a world that requires time and technological investment to develop low-cost greenhouse gas emission offsets.” AF GHG emission mitigation is sensitive to saturation of sequestration sinks. This research finds that ignoring saturation characteristics leads to a severe overestimate of mitigation potential with estimates being inflated by as much as a factor of 6.
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System studies of forest-based biomass gasificationWetterlund, Elisabeth January 2012 (has links)
Bioenergy will play an important role in reaching the EU targets for renewable energy. Sweden, with abundant forest resources and a well-established forest industry, has a key position regarding modern biomass use. Biomass gasification (BMG) offers several advantages compared to biomass combustion-based processes, the most prominent being the possibility for downstream conversion to motor fuels (biofuels), and the potential for higher electrical efficiency if used for electricity generation in a biomass integrated gasification combined cycle (BIGCC). BMG-based processes in general have a considerable surplus of heat, which facilitates integration with district heating or industrial processes. In this thesis integration of large-scale BMG, for biofuel or electricity production, with other parts of the energy system is analysed. Focus is on forest-based biomass, with the analysis including techno-economic aspects as well as considerations regarding effects on global fossil CO2 emissions. The analysis has been done using two approaches – bottom-up with detailed case studies of BMG integrated with local systems, and top-down with BMG studied on a European scale. The results show that BMG-based biofuel or electricity production can constitute economically interesting alternatives for integration with district heating or pulp and paper production. However, due to uncertainties concerning future energy market conditions and due to the large capital commitment of investment in BMG technology, forceful economic support policies will be needed if BMG is a desired route for the future energy system, unless oil and electricity prices are high enough to provide sufficient incentives for BMG-based biofuel or electricity production. While BMG-based biofuel production could make integration with either district heating or pulp and paper production economically attractive, BIGCC shows considerably more promise if integrated with pulp and paper production than with district heating. Bioenergy use is often considered CO2-neutral, because uptake in growing plants is assumed to fully balance the CO2 released when the biomass is combusted. As one of the alternatives in this thesis, biomass is viewed as limited. This means that increased use of bioenergy in one part of the energy system limits the amount of biomass available for other applications, thus increasing the CO2 emissions for those applications. The results show that when such marginal effects of increased biomass use are acknowledged, the CO2 mitigation potential for BMG-based biofuel production becomes highly uncertain. In fact, most of the BMG-based biofuel cases studied in this thesis would lead to an increase rather than the desired decrease of global CO2 emissions, when considering biomass as limited. / Bioenergi spelar en viktig roll för att nå EU:s mål för förnybar energi. Sverige har med sina goda skogstillgångar och sin väletablerade skogsindustri en nyckelposition vad gäller modern bioenergianvändning. Förgasning av biomassa har flera fördelar jämfört med förbränningsbaserade processer - i synnerhet möjligheten att konvertera lågvärdiga råvaror till exempelvis fordonsdrivmedel. Används gasen istället för elproduktion kan en högre verkningsgrad nås om gasen används i en kombicykel, jämfört med i en konventionell ångturbincykel. De förgasningsbaserade processerna har i allmänhet ett betydande överskott av värme, vilket möjliggör integrering med fjärrvärmesystem eller industriella processer. I denna avhandling analyseras integrering av storskalig biomassaförgasning för drivmedelseller elproduktion, med andra delar av energisystemet. Skogsbaserad biomassa är i fokus och analysen behandlar såväl teknoekonomiska aspekter, som effekter på globala fossila CO2-utsläpp. Forskningen har gjorts på två olika systemnivåer - dels i form av detaljerade fallstudier av biomassaförgasning integrerat med lokala svenska system, dels i form av systemstudier på europeisk nivå. Resultaten visar att förgasningsbaserad biodrivmedels- eller elproduktion kan komma att utgöra ekonomiskt intressanta alternativ för integrering med fjärrvärme eller massa- och papperstillverkning. På grund av osäkerheter i fråga om framtida energimarknadsförhållanden och på grund av de höga kapitalkostnaderna som investering i förgasningsanläggningar innebär, kommer kraftfulla ekonomiska styrmedel krävas om biomassaförgasning är en önskad utvecklingsväg för framtidens energisystem, såvida inte olje- och elpriserna är höga nog att i sig skapa tillräckliga incitament. Medan förgasningsbaserad drivmedelsproduktion kan vara ekonomiskt attraktivt att integrera med såväl fjärrvärme som med massa- och papperstillverkning, framstår förgasningsbaserad elproduktion som betydligt mer lovande vid integrering med massa- och papperstillverkning. Användning av bioenergi anses ofta vara CO2-neutralt, eftersom upptaget av CO2 i växande biomassa antas balansera den CO2 som frigörs när biomassan förbränns. Som ett av alternativen i denna avhandling ses biomassa som begränsad, vilket innebär att ökad användning av bioenergi i en del av energisystemet begränsar den tillgängliga mängden biomassa för andra användare, vilket leder till ökade CO2-utsläpp för dessa. Resultaten visar att när hänsyn tas till denna typ av marginella effekter av ökad biomassaanvändning, blir potentialen för minskade globala CO2-utsläpp med hjälp av förgasningsbaserade tillämpningar mycket osäker. I själva verket skulle de flesta av de förgasningsbaserade drivmedel som studerats i denna avhandling leda till en utsläppsökning, snarare än den önskade minskningen.
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Dynamic Parenting: Ethnic Identity Construction in the Second-Generation Indian American FamilySinha, Cynthia B. 19 November 2010 (has links)
This study explores Indian culture in second-generation Indian American families. For the most part, this generation was not socialized to Indian culture in India, which raises the question, how do parents maintain and teach culture to their third-generation children? To answer this question, I interviewed 18 second-generation Indian American couples who had at least one child. Rather than focus on how assimilated or Americanized the families were, I examine the maintenance of Indian culture. Instead of envisioning culture as a binary between “Indian” and “American,” second-generation parents often experience “Indianness” and “Americanness” as interwoven in ways that were not always easily articulated. I also explore the co-ethnic matrimonial process of my participants to reveal the salience of Indian-American identity in their lives. A common experience among my participants was the tendency of mainstream American non- Indians to question Indian-Americans about India and Indian culture. My participants frequently were called upon to be “cultural ambassadors” to curious non-Indians. Religion served as a primary conduit for teaching Indian culture to third-generation children. Moreover, religion and ethnic identity were often conflated. Mothers and fathers share the responsibility of teaching religion to third-generation children. However, mothers tend to be the cultural keepers of the more visible cultural objects and experiences, such as, food, clothing, and language. Fathers were more likely to contribute to childcare than housework. The fathers in my study believe they father in a different social context than their fathers did. By negotiating Indian and American culture, fathers parent in a way that capitalizes on what they perceive as the “best of both worlds.” Links to the local and transnational community were critical to maintaining ties to other co-ethnics and raising children within the culture. Furthermore, most of the parents in my study said they would prefer that their children eventually marry co-ethnics in order to maintain the link to the Indian-American community. Ultimately, I found that Indian culture endures across first- and second-generation Indian Americans. However, “culture” is not a fixed or monolithic object; families continue to modify traditions to meet their emotional and cultural needs.
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The role of US agricultural and forest activities in global climate change mitigationZhu, En 15 May 2009 (has links)
In 2005 the highest global surface temperature ever was recorded. A virtual consensus exists today among scientists that global warming is underway and that human greenhouse gas (GHG) emissions are a significant cause. Possible mitigation of climate change through reduction of net GHG emissions has become a worldwide concern. Under the United Nation’s Framework convention on Climate Change, the Kyoto Protocol was formed in 1997 and required ratifying countries to co-operate in stabilizing atmospheric GHG concentrations. The protocol took effect on February 16, 2005. The mitigation cost for reducing GHG emissions for the US economy has been argued to be high particularly through the energy sector. Agriculture and Forestry (AF) can provide some low cost strategies to help with this mitigation principally through carbon sequestration but must be competitive with mitigation costs in the rest of the economy. A general equilibrium approach is used herein to evaluate the role of AF mitigation in an economy wide setting. The results show that the AF sectors have significant mitigation potential. Higher carbon prices lead to more sequestration, less emissions, reduced consumer and total welfare, improved environmental indicators and increased producer welfare. AF mitigation increases as the carbon price increase over time. In the earlier periods, while the carbon price is low, AF emissions and sink are quite small compared to the energy sector. As carbon prices increase over time, the AF sectors mitigate about 25% of the net emissions. This verifies McCarl et al's (2001) argument that the AF sectors “may be very important in a world that requires time and technological investment to develop low-cost greenhouse gas emission offsets.” AF GHG emission mitigation is sensitive to saturation of sequestration sinks. This research finds that ignoring saturation characteristics leads to a severe overestimate of mitigation potential with estimates being inflated by as much as a factor of 6.
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Competitive Strategies from 2G to 3G¡V A case of Taiwan Mobile GroupLee, Pen-nan 22 January 2008 (has links)
Abstract
Competitive Strategies from 2G to 3G
¡V A case of Taiwan Mobile Group
In trend with WTO, globalization and government policy, the domestic
telecommunication market has gradually moved from monopoly to free market.
Suddenly, the liberalization of telecommunication resulted in fierce competitions in the
market, each fighting for customers and market share, staging a battle scene in the
telecommunication industry.
Although 2G has excelled, it could not lead the fixed network out of its
distress. Business enterprises were still stuck in the swamp of the last mile. On the other
hand, 3G was launched with a thunderbolt posture, but its expensive license fee has
deeply scarred business enterprises once again. Competitors tried their best in both hard
selling and lucrative promotions, only to find very few customers have been touched.
Money has been spent, but the future seems dim.
Faced with a chaotic market, fierce competition and a hazy future of 3G market,
how the telecommunication business enterprises innovate new business models,
provide attractive service content to consumers, so as to avoid fierce price competition
and establish new competitive advantage, the business mindset, strategic positioning
are crux of the matter. In Porter¡¦s Competitive Strategies, the objective of competitive
strategy is to be different. In other words, when a business manager establishes a
different set of business activities, provides a unique set of values to customers, can it
thus have a unique competitive advantage.
Taiwan Mobile Group is one of the three largest domestic telecommunications
company. Its scope of business includes fixed network, cellular network, 2G and 3G
mobile telecommunication, customer service and all other telecommunication
businesses since the liberalization of the industry. The business team ¡V Fubon Financial
- is one of the top business group in Taiwan. Is its factor of success in 2G one of
internal advantage or one of external opportunity? What is its competitive strategy from
2G to 3G? Can its success in 2G ensure similar success in a competitive advantageous
position in the 3G and future market? Faced with a slow development of 3G market,
lack of competitiveness in the service function, as well as the impact of 4G WiMAX
V
technology, what kind of strategic posture should it take?
This thesis investigates the development of Taiwan Mobile Group from 2G to 3G,
its strategic positioning, internal competitiveness and how it should innovate a new
business model, establish a different set of business activities, or provide unique service
value, so as to create an unique competitive advantage, to reap greater market
opportunities and continually create competitive advantage.
Six conclusions are made for the case study company: (1) The success of 2G is
the strength and foundation for Taiwan Mobile Group in the 3G market. (2) The
development of Triple Play digital bus cross-industry system integration aids in the
competitive advantage of 3G. (3) Merger strategy and resource integration strategy may
not achieve synergy. (4) Corporate governance has poor results, unclear vision does not
aid the long term development of the business. (5) Concern for employee should take a
higher priority than focus on customers. (6) Dependence on external technology and
lack of R&D capability do not facilitate development of continuous competitive
advantage.
Eight recommendations to the case study company: (1) Research and develop a
killer ¡§integrated mobile digital service platform¡¨ to dominate the 3G and markets of
the future. (2) Cultivate senior management with skills in innovation and integration. (3)
Institute a forward-looking ¡§vision¡¨ to lead its employees, inspire passion and seize the
future. (4) Build up a corporate culture of ¡§customer is paramount¡¨, ¡§employee first¡¨,
and ¡§continued business operation¡¨. (5) Decentralize the organization, humanistic
management, simplify process, rationalized costs. (6) Construct a ¡§business resource
integration platform¡¨ to integrate all internal resources and build up a strong
competitive force. (7) Cultivate the ¡§corporate client¡¨ market. (8) Plans moves in China
with a global vision.
Further studies:
(1) Study of the competition and cooperation strategies between 3G and WiMAX.
(2) How does Taiwan innovate an ¡§integrated mobile digital service platform¡¨.
Keyword: Competitive Strategy, Competitive Advantage, Second Generation Mobile
Telephony (2G), Third Generation Mobile Telephony (3G)
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A Study of Employment and Treatment Problems of Migrant Workers in Urban ChinaTsai, Yun-Pei 02 September 2009 (has links)
Migrant workers' inequality generates many social issues like Why Migrant workers' children spend more tuition in cities than urban workers' ones since they are all Chinese? As workers in cities shared with the same workload and hours, why migrant workers can only obtain low wages, less job offers and exclusion from social security? In the circumstance of financial crisis, why migrant workers are the first to be unemployed? These long-standing issues always cause social concern and accordingly become motives for the study.
The article not only describes migrant workers' livelihood, but also aims at the comparative study between them and urban workers. The finding demonstrated migrant workers are relatively weak upon wages, employment opportunity, their children 's education level and social welfare. Such unfair treatment could be attributed to migrant workers' identity problems¡Bhighly variable labor market and incomplete policy implementation. China 's economy and related policy changes yearly since its reform and opening-up policy, however, they are not fully consider migrant workers factor. Besides, limited with its self-interest, local government's policy implementation shows discrepancy from central counterpart's intention. With vicious circle potential which might affect society in many aspects, government should focus on migrant workers' unfair treatment improvement. The research finding could benefit reader's comprehensive understanding upon migrant workers' core issues. Furthermore, China government's solution could be meaningful references for the improvement of Taiwanese business's migrant workers treatment and Taiwan government's foreign-labor policy.
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