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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Functional data analysis in orthogonal designs with applications to gait patterns

Zhang, Bairu January 2018 (has links)
This thesis presents a contribution to the active research area of functional data analysis (FDA) and is concerned with the analysis of data from complex experimental designs in which the responses are curves. High resolution, closely correlated data sets are encountered in many research fields, but current statistical methodologies often analyse simplistic summary measures and therefore limit the completeness and accuracy of conclusions drawn. Specifically the nature of the curves and experimental design are not taken into account. Mathematically, such curves can be modelled either as sample paths of a stochastic process or as random elements in a Hilbert space. Despite this more complex type of response, the structure of experiments which yield functional data is often the same as in classical experimentation. Thus, classical experimental design principles and results can be adapted to the FDA setting. More specifically, we are interested in the functional analysis of variance (ANOVA) of experiments which use orthogonal designs. Most of the existing functional ANOVA approaches consider only completely randomised designs. However, we are interested in more complex experimental arrangements such as, for example, split-plot and row-column designs. Similar to univariate responses, such complex designs imply that the response curves for different observational units are correlated. We use the design to derive a functional mixed-effects model and adapt the classical projection approach in order to derive the functional ANOVA. As a main result, we derive new functional F tests for hypotheses about treatment effects in the appropriate strata of the design. The approximate null distribution of these tests is derived by applying the Karhunen- Lo`eve expansion to the covariance functions in the relevant strata. These results extend existing work on functional F tests for completely randomised designs. The methodology developed in the thesis has wide applicability. In particular, we consider novel applications of functional F tests to gait analysis. Results are presented for two empirical studies. In the first study, gait data of patients with cerebral palsy were collected during barefoot walking and walking with ankle-foot orthoses. The effects of ankle-foot orthoses are assessed by functional F tests and compared with pointwise F tests and the traditional univariate repeated-measurements ANOVA. The second study is a designed experiment in which a split-plot design was used to collect gait data from healthy subjects. This is commonly done in gait research in order to better understand, for example, the effects of orthoses while avoiding confounded analysis from the high variability observed in abnormal gait. Moreover, from a technical point of view the study may be regarded as a real-world alternative to simulation studies. By using healthy individuals it is possible to collect data which are in better agreement with the underlying model assumptions. The penultimate chapter of the thesis presents a qualitative study with clinical experts to investigate the utility of gait analysis for the management of cerebral palsy. We explore potential pathways by which the statistical analyses in the thesis might influence patient outcomes. The thesis has six chapters. After describing motivation and introduction in Chapter 1, mathematical representations of functional data are presented in Chapter 2. Chapter 3 considers orthogonal designs in the context of functional data analysis. New functional F tests for complex designs are derived in Chapter 4 and applied in two gait studies. Chapter 5 is devoted to a qualitative study. The thesis concludes with a discussion which details the extent to which the research question has been addressed, the limitations of the work and the degree to which it has been answered.
2

Metodologias para reconhecimento de padrões em sistemas SHM utilizando a técnica da Impedância Eletromecânica (E/M) /

Gonsalez, Camila Gianini. January 2012 (has links)
Orientador: Vicente Lopes Junior / Banca: Samuel Silva / Banca: Michael John Brennan / Banca: Carlos Alberto Cimini Junior / Resumo: Pesquisadores de diversas partes do mundo se empenham em desenvolver técnicas capazes de monitorar a integridade de máquinas, veículos e estruturas, principalmente as que a ruptura ou destruição possa provocar acidentes e catástrofes. Neste contexto, várias técnicas não destrutivas podem ser utilizadas para monitorar estes sistemas permitindo a realização de reparos e, evitando maiores prejuízos econômicos e danos sociais. A técnica da Impedância Eletromecânica está entre as técnicas baseadas na utilização de materiais piezelétricos e, particularmente, utiliza-se de uma curva sensível a pequenas variações na estrutura, característica que faz a técnica ser eficiente na detecção de danos incipientes. No entanto, sob variações das condições ambiente e de teste, a sensibilidade da técnica pode produzir falsos diagnósticos. Desta forma, o desafio atual é aplicar a técnica da Impedância Eletromecânica em sistemas de monitoramento considerando condições mais próximas às condições de operação reais dos sistemas a serem monitorados. Este trabalho apresenta duas metodologias para sistemas SHM, a primeira consiste em utilizar a técnica de agrupamento Fuzzy c-means para entender e considerar o efeito da temperatura nos sinais da Impedância Eletromecânica. A segunda metodologia utiliza análise de variância (ANOVA) para propor uma metodologia de detecção mais robusta, e assim, incorporar variações aleatórias nos sistemas de medição e aquisição sem comprometer o diagnóstico SHM / Abstract: Researchers around the world are engaged to develop techniques for structural health monitoring of machinery, vehicles and structures, especially systems where damage or destruction could induce accidents and disasters. In this context, several non-destructive techniques can be used to monitor these systems allowing repairs and avoiding major economic losses or social losses. The electromechanical impedance technique is among the techniques based on piezoelectric materials use and it is sensible to small variations in the structure which makes it efficient in detecting incipient damages. However, variations in the ambient or test conditions can cause false diagnoses. Therefore, the current challenge is to apply the electromechanical impedance technique considering monitoring conditions closer to real operating conditions of the systems to be monitored. This work presents two methodologies for SHM systems. The first one uses Fuzzy c-means clustering to distinguish the temperature effect on impedance signal. The second method uses analysis of variance (ANOVA) to propose a more robust detection methodology and thus incorporate random variations in measurement systems and acquisition without loss of SHM diagnostic / Mestre
3

Metodologias para reconhecimento de padrões em sistemas SHM utilizando a técnica da Impedância Eletromecânica (E/M)

Gonsalez, Camila Gianini [UNESP] 24 February 2012 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:27:13Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-02-24Bitstream added on 2014-06-13T19:14:27Z : No. of bitstreams: 1 gonsalez_cg_me_ilha.pdf: 4679748 bytes, checksum: 5f6a627734b2110f92059053c2470814 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Pesquisadores de diversas partes do mundo se empenham em desenvolver técnicas capazes de monitorar a integridade de máquinas, veículos e estruturas, principalmente as que a ruptura ou destruição possa provocar acidentes e catástrofes. Neste contexto, várias técnicas não destrutivas podem ser utilizadas para monitorar estes sistemas permitindo a realização de reparos e, evitando maiores prejuízos econômicos e danos sociais. A técnica da Impedância Eletromecânica está entre as técnicas baseadas na utilização de materiais piezelétricos e, particularmente, utiliza-se de uma curva sensível a pequenas variações na estrutura, característica que faz a técnica ser eficiente na detecção de danos incipientes. No entanto, sob variações das condições ambiente e de teste, a sensibilidade da técnica pode produzir falsos diagnósticos. Desta forma, o desafio atual é aplicar a técnica da Impedância Eletromecânica em sistemas de monitoramento considerando condições mais próximas às condições de operação reais dos sistemas a serem monitorados. Este trabalho apresenta duas metodologias para sistemas SHM, a primeira consiste em utilizar a técnica de agrupamento Fuzzy c-means para entender e considerar o efeito da temperatura nos sinais da Impedância Eletromecânica. A segunda metodologia utiliza análise de variância (ANOVA) para propor uma metodologia de detecção mais robusta, e assim, incorporar variações aleatórias nos sistemas de medição e aquisição sem comprometer o diagnóstico SHM / Researchers around the world are engaged to develop techniques for structural health monitoring of machinery, vehicles and structures, especially systems where damage or destruction could induce accidents and disasters. In this context, several non-destructive techniques can be used to monitor these systems allowing repairs and avoiding major economic losses or social losses. The electromechanical impedance technique is among the techniques based on piezoelectric materials use and it is sensible to small variations in the structure which makes it efficient in detecting incipient damages. However, variations in the ambient or test conditions can cause false diagnoses. Therefore, the current challenge is to apply the electromechanical impedance technique considering monitoring conditions closer to real operating conditions of the systems to be monitored. This work presents two methodologies for SHM systems. The first one uses Fuzzy c-means clustering to distinguish the temperature effect on impedance signal. The second method uses analysis of variance (ANOVA) to propose a more robust detection methodology and thus incorporate random variations in measurement systems and acquisition without loss of SHM diagnostic
4

Factors influencing the degree of burnout experienced by nurses working in neonatal intensive care units

Joubert, Ronel 03 1900 (has links)
Thesis (MCur)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: Burnout is one of the challenges that nurses are faced with in their stressful and rapidly changing work environment. The vulnerability of nurses to burnout remains a major concern which affects both the individual and institution. Knowledge about burnout and associated risk factors which influence the development of burnout is vital for early recognition and intervention. The research question which guided this study was: “What are the factors influencing the degree of burnout experienced by nurses working in neonatal intensive care units?” The objectives included determining which physical, psychological, social and occupational factors influenced the degree of burnout experienced by nurses. A descriptive, explorative research design with a quantitative approach was applied. The target population consisted of (n=105) permanent nursing staff members working in the neonatal units of two different hospitals. A convenience sampling method was used. Participants (n=102) who gave voluntary consent to participate was included in the study. Validity and reliability was supported through the use of a validated questionnaire, Maslach Burnout Inventory – General Survey including a section based on demographical information and a section based on physical, psychosocial, social and occupational factors. Validity of the questionnaire was supported by the use of a research methodologist, nurse expert and a statistician in the particular field. A pilot study was done to test the feasibility of the study and to test the questionnaire for any errors and ambiguities. Ethics approval was obtained from Stellenbosch University and permission from the Heads of the hospitals where the study was conducted. The data was analyzed with the assistance of a statistician and these are presented in histograms, tables and frequencies. The relationship between response variables and nominal input variables was analysed using analysis of variance (ANOVA). Various statistical tests were applied to determine statistical associations between variables such as the Spearman test, using a 95% confidence interval. Results have shown that participants experienced an average level of emotional exhaustion, a high level of professional efficacy and a low level of cynicism. Further analyses have shown that there is a statistical significant difference between emotional exhaustion and the rank of the participant (p=<0.01), highest qualification (p=0.05) and a high workload (p=0.01). Furthermore a statistical significant difference was found between professional efficacy and rank of participants (p=<0.01). In addition a statistical significant difference was found between cynicism and the number of years participants were in the profession (p=0.05). Multiple factors were determined in this study that influences the degree of burnout nurses experience. The majority of participants (n=56/55%) experienced decreased job satisfaction and accomplishment, (n=52/51%) of participants experienced that their workload is too much for them and (n=63/62%) participants received no recognition for their work. Recommendations are based on preventative measures, because preventing burnout is easier and more cost-effective than resolving burnout once it has occurred. In conclusion, the prevention strategies, early recognition of work stress and appropriate interventions are crucial in addressing the problem of burnout. / AFRIKAANSE OPSOMMING: Uitbranding is een van die uitdagings waarmee verpleegsters te kampe het in hulle stresvolle en vinnig veranderende werkomgewing. Die kwesbaarheid van verpleegsters vir uitbranding bly ’n kritieke bekommernis wat beide die individu en die inrigting affekteer. Kennis omtrent uitbranding en verwante risiko faktore wat die ontwikkeling van uitbranding beïnvloed, is deurslaggewend vir vroeë opsporing en intervensie. Die navorsingsvraag wat hierdie studie gelei het, is: “Wat is die faktore wat die mate van uitbranding beïnvloed wat deur verpleegsters ondervind word wat in neonatale intensiewe sorgeenhede werk?” Die doelwitte wat ingesluit is, is om te bepaal watter fisiese, sielkundige, maatskaplike en beroepsfaktore die mate van uitbranding wat deur verpleegsters ervaar word, beïnvloed. ’n Beskrywende, ondersoekende navorsingsontwerp met ’n kwantitatiewe benadering is toegepas. Die teikengroep het bestaan uit (n=105) permanente verpleegpersoneel wat in die neonatale eenhede van twee verskillende hospitale werk. ’n Gerieflikheidsteekproef metode is gebruik. Deelnemers (n=102) wat vrywillige toestemming gegee het om deel te neem, is ingesluit in die navorsingstudie. Geldigheid en betroubaarheid is ondersteun deur die gebruik van ’n geldige vraelys van “Maslach Burnout Inventory – General Survey”, asook ’n afdeling gebaseer op demografiese inligting en ’n afdeling gebaseer op fisiese, sielkundige, maatskaplike en beroepsfaktore. Geldigheid van die vraelys is ondersteun deur ’n navorsingsmetodoloog, ’n verpleegspesialis en ’n statistikus op die navorsingsgebied. ’n Loodsondersoek is gedoen om die haalbaarheid van die studie te toets en om die vraelys te toets vir enige foute en dubbelsinnighede. Etiese goedkeuring is verkry van die Universiteit van Stellenbosch en goedkeuring van die Hoofde van die hospitale waar die studie uitgevoer is. Die data is geanaliseer met die hulp van ’n statistikus en is aangebied in histogramtafels en frekwensies. Die verwantskap tussen responsveranderlikes en nominale insetveranderlikes is geanaliseer deur gebruik te maak van die analise van variansie (ANOVA). Verskeie statistiese toetse is toegepas om statistiese assosiasies tussen veranderlikes te bepaal, soos deur van die Spearmantoets gebruik te maak, met ’n 95% betroubaarheidsinterval. Resultate het bewys dat deelnemers ’n gemiddelde vlak van emosionele uitputting, ’n hoë vlak van professionele effektiwiteit en ’n lae vlak van sinisme ervaar. Verdere analise het bewys dat daar ’n statistiese beduidende verskil tussen emosionele uitputting en die rang van die deelnemers (p=<0.01) is, hoogste kwalifikasie (p=0.05) en ’n hoë werklading (p=0.01). Verder is ’n statistiese beduidende verskil gevind tussen professionele effektiwiteit en rang van deelnemers (p=<0.01). Saam hiermee is ’n statistiese beduidende verskil gevind tussen siniesheid en die aantal jare wat deelnemers in die beroep is (p=0.05). Voorts, is veelvuldige faktore bepaal in hierdie studie wat die mate van uitbranding beïnvloed wat verpleegsters ervaar. Die meeste van die deelnemers (n=56/55%) het ’n afname in werksbevrediging en -verrigting ervaar, (n=52/51%) deelnemers het ervaar dat hul werklading te veel is vir hulle en (n=63/62%) deelnemers het geen erkenning vir hulle werk ontvang nie. Aanbevelings is gebaseer op voorkomende maatreëls, want om uitbranding te voorkom, is makliker en meer koste-effektief as om uitbranding te probeer oplos as dit alreeds begin het. Ten slotte, die voorkomende strategieë, vroeë identifisering van werkstres en geskikte intervensies is deurslaggewend om die probleem van uitbranding aan te spreek.
5

Painéis de alta densidade para aplicação em pisos: produção e avaliação de desempenho / High density panels for application in floors: production and performance evaluation

Varanda, Luciano Donizeti 12 September 2016 (has links)
Temas relacionados ao desenvolvimento de novos materiais têm sido cada vez mais abordados e discutidos, num contexto em que questões como meio ambiente, sociedade, economia de energia e aproveitamento de resíduos, vêm se tornando relevantes. Neste cenário, faz-se necessário estudar aplicações de insumos alternativos na produção de pisos de madeira, tanto para reduzir o consumo de essências tropicais quanto para suprir o aumento da demanda de madeira nas indústrias deste segmento. O objetivo deste estudo foi produzir painéis de partículas homogêneos de alta densidade, com resíduos de madeira de Pinus elliottii e casca de aveia (Avena sativa), aderidos sob pressão com dois tipos de adesivo, poliuretano à base de óleo de mamona e melamina formaldeído, nos percentuais de 11 e 13%, e avaliar o desempenho físico-mecânico de tais painéis para aplicação em pisos. O desempenho físico-mecânico dos painéis (Planejamento I - 20 tratamentos) foi avaliado com base nas normas ABNT NBR 14810 (2006 e 2013). Realizou-se análise de variância (ANOVA) para testar a influência dos fatores individuais (percentual de casca de aveia, percentual de adesivo e tipo de adesivo), além das interações entre tais fatores (dois a dois e três a três) nas propriedades físico-mecânicas dos painéis. Também foi avaliado o desempenho para pisos, tanto dos painéis (Planejamento II - 12 tratamentos) quanto de três espécies de madeira tropical (Angelim Vermelho, Dinizia excelsa; Cumaru, Dipteryx odorata e Jatobá, Hymenaea sp.), segundo diversas normas relacionadas a pisos de madeira. Os resultados apontaram propriedades físico-mecânicas dos painéis, em alguns tratamentos superiores aos requisitos estipulados por normas nacionais e internacionais. Quanto ao desempenho para pisos, os painéis apresentaram desempenho semelhante as três espécies de madeira, na maioria das propriedades avaliadas. A análise de porosimetria por intrusão de mercúrio confirmou a similaridade entre os painéis (do Planejamento II) e as três espécies de madeira avaliadas, evidenciando a potencialidade dos painéis produzidos para aplicação na indústria de pisos engenheirados. / Matters related to the development of new materials have been increasingly addressed and discussed in a context where issues such as the environment, society, energy and waste recovery economy, is becoming relevant. In this scenario, it is necessary to study alternative inputs for applications in the production of wood floors, both to reduce the consumption of tropical essences as to meet the increasing demand for wood in industries in this segment. The aim this study was to produce high density homogeneous particleboard with waste wood of Pinus elliottii and oat hulls (Avena sativa), adhered under pressure with two types of adhesive, castor oil-based polyurethane and melamine formaldehyde, the percentage of 11 and 13%, and evaluate the physical and mechanical performance of such panels for use in floors. The physical-mechanical performance of the panels (Planning I - 20 treatments) was evaluated based on the NBR 14810 (2006 and 2013) standards. We conducted an analysis of variance (ANOVA) to evaluate the influence of individual factors (oat hulls percentage, adhesive percentage and type of adhesive), and the interactions between these factors (two by two and three by three) on the physical properties-mechanical panels. It was also evaluated the performance for floors, both panels (Planning II - 12 treatments) as three species of tropical wood (Angelim Vermelho, Dinizia excelsa; Cumaru, Dipteryx odorata e Jatobá, Hymenaea sp.), according to various standards related to wood floors. The results indicated physical and mechanical properties of the panels, in some treatments superior to the requirements stipulated by national and international standards. As for performance flooring, panels statistically equivalent to the three species of wood, most of the evaluated properties. Porosimetry analysis by mercury intrusion confirmed the similarity between the panels (from Planning II) and the three wood species evaluated, demonstrating the potential of the panels produced for use in the flooring industry engineered.
6

Produção e avaliação do desempenho de painéis de partículas de Eucalyptus grandis confeccionados com adição de casca de aveia / Production and performance evaluation of particleboard made from Eucalyptus grandis addition of oat hulls

Varanda, Luciano Donizeti 10 July 2012 (has links)
Os painéis à base de madeira vêm sendo amplamente utilizados em todo o mundo, em resposta à redução de oferta de madeira maciça em diversos segmentos da indústria madeireira, como em móveis, painéis, estruturas e outros componentes na construção civil. O grande volume de resíduos gerados pela agroindústria viabiliza o desenvolvimento de materiais alternativos e sustentáveis, destacando-se os painéis de partículas. Este trabalho apresenta um estudo da produção e avaliação de painéis de partículas de Eucalyptus grandis e casca de aveia, aderidas sob pressão com dois tipos de resinas (poliuretana à base de mamona e ureia formaldeído). O desempenho físico-mecânico dos painéis produzidos foi avaliado com base na ABNT NBR 14810:2006. Por meio de análise de variância (ANOVA), avaliou-se a influência dos fatores adotados: madeira de Eucalyptus grandis, com proporções mássicas de 70, 85 e 100%; casca de aveia, nas proporções de 15, 30 e 100%; e adesivos, nas proporções de 10, 12 e 14%, bem como a combinação entre ambos, em cada uma das variáveis respostas (propriedades físico-mecânicas) avaliadas. Os resultados apontaram excelentes propriedades físico-mecânicas, em alguns casos muito superiores aos requisitos estipulados pelas normas nacionais e internacionais. Desta maneira, ficou comprovado o bom desempenho dos painéis de partículas produzidos, além de sua compatibilidade para aplicações em indústrias, como de móveis, painéis, embalagens e na construção civil. / Wood-based panels have been widely used around the world, replacing solid wood in various segments of the industry, such as furniture, panels, structures and other building components. The large volume of waste generated by agro industry enables the development of alternative and sustainable materials, highlighting the particleboard. This paper presents a study about production and evaluation of particleboard of Eucalyptus grandis and oat hulls, bonded under pressure with two types of resins (polyurethane based on castor oil and urea formaldehyde). Physical-mechanical performance of the panels produced was evaluated based on ABNT NBR 14810:2006. A variance analysis (ANOVA) evaluated the factors influence: Eucalyptus grandis, with mass ratios of 70, 85 and 100%; oat hulls, in proportions of 15, 30 and 100%; adhesives, in proportions of 10, 12 and 14%, and the combination of both, in each of the response variables (physical and mechanical properties) evaluated. Results showed excellent physical-mechanical properties, in some cases much higher than national and international codes requirements. Thus, panel particles good performance was proved, in addition to its compatibility with applications in wood industries, such as furniture, panels, packaging and in building construction.
7

台灣綠色電價政策之關鍵因素研究 / The Study on Key Factors of the Green Power Pricing Policy in Taiwan

陳秋伶, Chen, Chiu Ling Unknown Date (has links)
為了因應全球暖化,鼓勵再生能源發展,先進國家逐步推動「綠色電價」。由於再生能源發電成本較一般傳統電力成本來得高,故再生能源電能之價格也會高於傳統電能之價格。對於高成本高售價之再生能源電能,多數國家在市場上透過用電戶自願認購方式進行銷售,並收取所謂的綠色電價,以作為綠色電力基金之來源,或作為未來發展再生能源之資金來源。透過這樣的制度,可以讓整體社會共同參與環境保護的工作,也可提高人民的環保意識和各界環境責任感,也可籌措再生能源發展所需的資金。 本研究透過問卷調查法,以網路問卷-Google Form發放,觀察並探討民眾對於綠色電價政策之購買意願,以及民眾對於當前政策之考量,透過ANOVA檢定,分析民眾填答問卷之結果,了解民眾本身對於環保問題的認知與意識,及民眾對於綠色電價政策之考量因素主要為何。根據問卷分析與檢定結果發現:多數民眾對於綠色電價的概念仍然相當模糊,但是大多會選擇購買綠色電價。 其次是對於本文所歸納的五個政策因素考量存有疑慮-政府政策宣導、綠色電價的制度設計、相關法規制定、執行單位之效能,以及支付額外的綠色電價對國人經濟上的負擔。五項當中,又以執行單位可能效能不佳之疑慮評分為最高。 本研究另外發現,民眾對於綠色電價的願付價格,接受度最高的是綠色電價比一般電價貴10%以下,意即在回收的221份問卷中,當綠電價格每度低於3.18元,一般民眾有五成以上會選購,與目前綠電價格設定3.96元存有落差。據此,在綠色電價政策推行上,和實際民眾購買意願之間,應該如何制訂一個合理的綠色電價,是需要仰賴國內產、官、學各界充分討論,以及民眾意見妥善表達,在國家與社會民眾間,取得一個平衡點,並且參考各先進國家發展自願性綠色電價之經驗。如此,方能在國家發展經濟的同時,又能兼顧環境保護和節能減碳,達到國家永續發展之政策目標。 / In response to global warming, the development of renewable energy is encouraged. Advanced countries are gradually promoting “green power pricing programs”. Due to the higher generating costs of renewable energy’s electricity than conventional one, therefore renewable energy electricity prices will be definitely higher than traditional electric energy prices. The high cost of renewable energy’s electricity pushes most countries in the market to sell this type of electricity to consumers through a voluntary subscription mode and charge a so-called green power pricing. Using green power as a source of funds or as the future development of renewable energy funding sources and with such a system, you can make the whole society participate in environmental protection work. People from all walks of life will have their environmental awareness and responsibility adequately improved. This study uses an online questionnaire-Google Form to survey, observe and explore the public’s reaction towards green power pricing policy, its willingness to purchase and its considerations for the current policies. Through the ANOVA test and the analysis of the results of the survey to understand the public’s cognition and awareness of environmental issues and the public’s main considerations towards the green power pricing policy, for most people such concept is still quite vague but anyhow they will choose to buy green. Secondly, this article summarizes five policy factors for consideration –doubts about government policy and advocacy, the designing of the green power pricing system, the related laws and regulations, the performance of the executive units and the payment of the green power pricing adding to the economic burden of the people. In the above five points, the poor performance of the units will, undoubtedly, carry the highest score. This study also found that the public is willing to pay for green power pricing and there is even a higher acceptance if the price would not exceed more than 10% of conventional electricity price. In other words, according to the response of 221 questionnaires, if the green power price lower than NT$3.18 /kWh, there will be half of people to purchase it. This study conducted a gap analysis between the current green power price-NT$3.96 /kWh and the price people accepted generally. Accordingly, the implementation of a policy on green electricity and the real willingness of the people to purchase such electricity depend on how reasonable the green tariff is. The industry, the government , the academia should all express their opinions. The state and the society must seek and strike a balance while referring to the development of green energy voluntary subscription tariffs in advanced countries. In this way, while simultaneously developing the economy of the country and taking into account the environment protection, energy saving and carbon reduction, we can reach our national goals of achieving a sustainable development.
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Painéis de alta densidade para aplicação em pisos: produção e avaliação de desempenho / High density panels for application in floors: production and performance evaluation

Luciano Donizeti Varanda 12 September 2016 (has links)
Temas relacionados ao desenvolvimento de novos materiais têm sido cada vez mais abordados e discutidos, num contexto em que questões como meio ambiente, sociedade, economia de energia e aproveitamento de resíduos, vêm se tornando relevantes. Neste cenário, faz-se necessário estudar aplicações de insumos alternativos na produção de pisos de madeira, tanto para reduzir o consumo de essências tropicais quanto para suprir o aumento da demanda de madeira nas indústrias deste segmento. O objetivo deste estudo foi produzir painéis de partículas homogêneos de alta densidade, com resíduos de madeira de Pinus elliottii e casca de aveia (Avena sativa), aderidos sob pressão com dois tipos de adesivo, poliuretano à base de óleo de mamona e melamina formaldeído, nos percentuais de 11 e 13%, e avaliar o desempenho físico-mecânico de tais painéis para aplicação em pisos. O desempenho físico-mecânico dos painéis (Planejamento I - 20 tratamentos) foi avaliado com base nas normas ABNT NBR 14810 (2006 e 2013). Realizou-se análise de variância (ANOVA) para testar a influência dos fatores individuais (percentual de casca de aveia, percentual de adesivo e tipo de adesivo), além das interações entre tais fatores (dois a dois e três a três) nas propriedades físico-mecânicas dos painéis. Também foi avaliado o desempenho para pisos, tanto dos painéis (Planejamento II - 12 tratamentos) quanto de três espécies de madeira tropical (Angelim Vermelho, Dinizia excelsa; Cumaru, Dipteryx odorata e Jatobá, Hymenaea sp.), segundo diversas normas relacionadas a pisos de madeira. Os resultados apontaram propriedades físico-mecânicas dos painéis, em alguns tratamentos superiores aos requisitos estipulados por normas nacionais e internacionais. Quanto ao desempenho para pisos, os painéis apresentaram desempenho semelhante as três espécies de madeira, na maioria das propriedades avaliadas. A análise de porosimetria por intrusão de mercúrio confirmou a similaridade entre os painéis (do Planejamento II) e as três espécies de madeira avaliadas, evidenciando a potencialidade dos painéis produzidos para aplicação na indústria de pisos engenheirados. / Matters related to the development of new materials have been increasingly addressed and discussed in a context where issues such as the environment, society, energy and waste recovery economy, is becoming relevant. In this scenario, it is necessary to study alternative inputs for applications in the production of wood floors, both to reduce the consumption of tropical essences as to meet the increasing demand for wood in industries in this segment. The aim this study was to produce high density homogeneous particleboard with waste wood of Pinus elliottii and oat hulls (Avena sativa), adhered under pressure with two types of adhesive, castor oil-based polyurethane and melamine formaldehyde, the percentage of 11 and 13%, and evaluate the physical and mechanical performance of such panels for use in floors. The physical-mechanical performance of the panels (Planning I - 20 treatments) was evaluated based on the NBR 14810 (2006 and 2013) standards. We conducted an analysis of variance (ANOVA) to evaluate the influence of individual factors (oat hulls percentage, adhesive percentage and type of adhesive), and the interactions between these factors (two by two and three by three) on the physical properties-mechanical panels. It was also evaluated the performance for floors, both panels (Planning II - 12 treatments) as three species of tropical wood (Angelim Vermelho, Dinizia excelsa; Cumaru, Dipteryx odorata e Jatobá, Hymenaea sp.), according to various standards related to wood floors. The results indicated physical and mechanical properties of the panels, in some treatments superior to the requirements stipulated by national and international standards. As for performance flooring, panels statistically equivalent to the three species of wood, most of the evaluated properties. Porosimetry analysis by mercury intrusion confirmed the similarity between the panels (from Planning II) and the three wood species evaluated, demonstrating the potential of the panels produced for use in the flooring industry engineered.
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Produção e avaliação do desempenho de painéis de partículas de Eucalyptus grandis confeccionados com adição de casca de aveia / Production and performance evaluation of particleboard made from Eucalyptus grandis addition of oat hulls

Luciano Donizeti Varanda 10 July 2012 (has links)
Os painéis à base de madeira vêm sendo amplamente utilizados em todo o mundo, em resposta à redução de oferta de madeira maciça em diversos segmentos da indústria madeireira, como em móveis, painéis, estruturas e outros componentes na construção civil. O grande volume de resíduos gerados pela agroindústria viabiliza o desenvolvimento de materiais alternativos e sustentáveis, destacando-se os painéis de partículas. Este trabalho apresenta um estudo da produção e avaliação de painéis de partículas de Eucalyptus grandis e casca de aveia, aderidas sob pressão com dois tipos de resinas (poliuretana à base de mamona e ureia formaldeído). O desempenho físico-mecânico dos painéis produzidos foi avaliado com base na ABNT NBR 14810:2006. Por meio de análise de variância (ANOVA), avaliou-se a influência dos fatores adotados: madeira de Eucalyptus grandis, com proporções mássicas de 70, 85 e 100%; casca de aveia, nas proporções de 15, 30 e 100%; e adesivos, nas proporções de 10, 12 e 14%, bem como a combinação entre ambos, em cada uma das variáveis respostas (propriedades físico-mecânicas) avaliadas. Os resultados apontaram excelentes propriedades físico-mecânicas, em alguns casos muito superiores aos requisitos estipulados pelas normas nacionais e internacionais. Desta maneira, ficou comprovado o bom desempenho dos painéis de partículas produzidos, além de sua compatibilidade para aplicações em indústrias, como de móveis, painéis, embalagens e na construção civil. / Wood-based panels have been widely used around the world, replacing solid wood in various segments of the industry, such as furniture, panels, structures and other building components. The large volume of waste generated by agro industry enables the development of alternative and sustainable materials, highlighting the particleboard. This paper presents a study about production and evaluation of particleboard of Eucalyptus grandis and oat hulls, bonded under pressure with two types of resins (polyurethane based on castor oil and urea formaldehyde). Physical-mechanical performance of the panels produced was evaluated based on ABNT NBR 14810:2006. A variance analysis (ANOVA) evaluated the factors influence: Eucalyptus grandis, with mass ratios of 70, 85 and 100%; oat hulls, in proportions of 15, 30 and 100%; adhesives, in proportions of 10, 12 and 14%, and the combination of both, in each of the response variables (physical and mechanical properties) evaluated. Results showed excellent physical-mechanical properties, in some cases much higher than national and international codes requirements. Thus, panel particles good performance was proved, in addition to its compatibility with applications in wood industries, such as furniture, panels, packaging and in building construction.
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Produção e avaliação do desempenho de compósitos à base de madeira a partir de insumos alternativos / Production and performance evaluation of wood-based composites from alternative inputs

Souza, Amós Magalhães de 11 November 2016 (has links)
A utilização de produtos provenientes de fontes renováveis e livres de substâncias tóxicas é tendência global, prova disso é o constante aumento da demanda por produtos à base de madeira. Segundo o Forest Products Statistics (2015), a produção mundial de painéis de madeira reconstituída, em 2014, foi de 388 milhões de m³, um aumento de 5,5% em comparação com o ano anterior e um aumento de 34% quando comparado com 2010. No entanto, o setor industrial de painéis de madeira há décadas enfrenta um grande desafio com relação às emissões tóxicas vindas dos adesivos convencionais. Diante destes problemas, a proposta do presente trabalho foi testar a viabilidade da produção de painéis aglomerados e painéis OSB, com significativa redução da emissão de formaldeído, a partir de resíduos de madeira de Pinus sp. e Tectona grandis (Teca). Neste sentido, buscou-se contribuir para o aumento do conhecimento científico sobre a utilização do polímero natural polihidroxibutirato (PHB) e do resíduo de tinta à base de resina epóxi como adesivos alternativos. Os painéis foram fabricados variando-se os parâmetros de produção para obtenção de melhores condições de processo, sendo estes: densidade baixa, média e alta; teor de adesivo de 20, 30 e 40%; adição de partículas de Teca nas proporções de 0, 25, 50, 75, 100%. O desempenho físico-mecânico dos painéis foi avaliado com base nas normas ABNT NBR 14810 (2013) e ANSI A208.1 (2009). Realizou-se análise de variância (ANOVA) para testar a influência dos fatores individuais (densidade, percentual de adesivo e fração de Teca), além das interações entre tais fatores nas propriedades físico-mecânicas dos painéis. Os resultados apontaram para excelentes propriedades físicas e mecânicas dos painéis aglomerados de média e alta densidade, tendo resíduo de tinta, principalmente, nas proporções de 30 e 40%. Na maioria dos casos as propriedades de tais painéis foram superiores aos requisitos estipulados pela norma brasileira e pelas internacionais. Assim, ficou confirmada a viabilidade de produção dos aglomerados com pelo menos um dos insumos estudados bem como seu potencial de emprego para as finalidades compatíveis com produtos desta natureza. / The use of products from renewable sources and free of toxic substances is a global trend, the proof is the steady increase in demand for wood-based products. According to the Forest Products Statistics (2015), world production of reconstituted wood panels in 2014 was 388 million cubic meters, an increase of 5.5% compared to the previous year and an increase of 34% compared to 2010. However, the industrial sector of wood panels for decades faces a major challenge with regard to toxic emissions coming from conventional adhesives. Faced with these problems, the purpose of this study was to test the feasibility of production of panels and OSB panels, with significant reduction of formaldehyde emissions from wood waste Pinus sp. and teak (Teak). In this sense, we sought to contribute to the increase of scientific knowledge on the use of natural polymer polyhydroxybutyrate (PHB) and residual ink resin-based epoxy as alternative adhesives. The panels were manufactured by varying the production parameters to obtain the best processing conditions, namely: low density, medium and high; resin content of 20, 30 and 40%; adding particles of Teak in proportions of 0, 25, 50, 75, 100%. The physical-mechanical performance of the panels was evaluated based on the standards NBR 14810 (2013) and ANSI A208.1 (2009). Held analysis of variance (ANOVA) to test the influence of individual factors (density, adhesive percentage and fraction Teak), and the interactions among these factors in the physical-mechanical properties of the panels. The results showed excellent physical and mechanical properties of the panels average clusters and high density, and ink residue, mainly in the proportions of 30 and 40%. In most cases the properties of these boards were superior to the requirements set by the Brazilian and international standards. Thus, it was confirmed production of agglomerates with at least one viability of inputs studied as well as their potential for employment for purposes compatible with products of this nature.

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